XXXVI Reunión Bienal de la Real Sociedad Española de Física

Europe/Madrid
Aula Magna (Santiago de Compostela, Facultade de Química)

Aula Magna

Santiago de Compostela, Facultade de Química

Av. das Ciencias s/n, 15701 Santiago de Compostela, A Coruña, Spain
Dolores Cortina (Universidade de Santiago de Compostela)
Description
The next Biennial Meeting of the RSEF will take place in Santiago de Compostela, from July 17th to 21st 2017. The meeting venue will be at the Faculty of Chemistry. This meeting follows those held in Gijón in 2015 and in Valencia in 2013.
    • 08:30 09:15
      Registration Hall Facultad de Química

      Hall Facultad de Química

      Santiago de Compostela, Facultade de Química

      Av. das Ciencias s/n, 15701 Santiago de Compostela, A Coruña, Spain
    • 09:15 13:20
      Plenary I Aula Magna

      Aula Magna

      Santiago de Compostela, Facultade de Química

      Av. das Ciencias s/n, 15701 Santiago de Compostela, A Coruña, Spain
      • 09:15
        Opening 45m
      • 10:00
        The European “Energy Transition” Revisited 50m
        There is worldwide consensus to reduce energy consumption and emissions of greenhouse gases in the atmosphere. The ‘energy transformation’ is surely one of the most important challenges of the 21st century. Correct planning and thorough insight into the complexities of energy systems are an absolute necessity before starting such a task, in order to avoid unnecessary disruptions in the economy and daily life of the citizens. The European Union has ambitious plans n this direction for the coming decades. However, there is no simple answer to the best way forward. In the electricity sector emphasis is currently put on massive developments in renewable systems (wind, solar, hydro, biomass,…). As wind and solar are main components, the consequences of the intermittency need to be fully understood. Important components for a green electricity system dominated by intermittent sources are still lacking and developing these is challenging and will take time. Therefore it is not justified to eliminate any of the non-renewable options in near future and future electricity policies. The plans of the EU need also to be shaped in the context of worldwide greenhouse gas emissions and estimated future world energy needs. The effectiveness of green electricity policies implemented in the EU so far will be discussed using the example of the Germany. A last but very important remark is about the information for the general public. Unfortunately, the quality of public and political discussions on this subject is a matter of great concern, as these frequently lack reference to realistic numbers, or use numbers very selectively. Even worse, critical discussions are very often simply ignored or rebuffed with unfounded black and white arguments. Given the importance of sufficient and high quality energy sources for the welfare of all citizens on this planet in the future, there is an important role for education. This should be an important asset in order to arrive at a correctly defined and affordable sustainable future energy supply.
        Speaker: Prof. Josef Ongena
      • 10:50
        Coffee break and poster session 30m
      • 11:20
        Tiny Objects and Big Science: Light and Shadows 50m
        The explanation of the nature and dynamics of visible matter present in the universe is one of the most successful theories in relativistic quantum physics. The discovery of the Higgs Boson in 2012 marked the end of a very fruitful era as well as the start of much more uncertain times. If the theory of particle physics stands out for its simplicity and beauty the experimental program, based on gigantic accelerators and particle detectors, paved the way for what now has become almost the standard in science, the big science. In this talk, I will present an overview the state of the art in the field of particle physics and the challenges ahead.
        Speaker: Prof. Teresa Rodrigo (IFCA)
      • 12:10
        FAIR - The Universe in the Laboratory 50m
        FAIR - The Universe in the Laboratory FAIR will be the next-generation facility for fundamental and applied research with antiprotons and ion beams. It will provide world-unique accelerator and experimental facilities, allowing for a great variety of unprecedented forefront research in physics and applied sciences. FAIR is an international project with 10 partner countries and more than 2500 scientists and engineers from more than 50 countries involved in the planning and construction of the accelerators and associated experiments. FAIR research focuses on the structure and evolution of matter on both a microscopic and a cosmic scale, bringing our Universe into one laboratory. In particular, FAIR with its four scientific pillars will expand the knowledge in various scientific fields beyond current frontiers, addressing the following: - The properties of the strong force and its role in shaping the basic building blocks of the visible world around us and in the evolution of the universe; - Test of symmetries and predictions of the Standard Models, as well as the search for physics beyond it; - The properties of matter under extreme conditions, at both the subatomic and the macroscopic scale of matter; and - Applications of high-intensity, high quality beams in research areas that provide the basis for, or indirectly address, issues of applied sciences and technology. In particular FAIR will open a new era in nuclear astrophysics. The talk will introduce FAIR, its unique scientific Opportunities, and the status of the realization of the project.
        Speaker: Prof. Paolo Giubelino
      • 13:00
        The RSEF Exterior Section 20m
        "Recently the RSEF has created an Exterior Section, aiming at representing the members that are staying abroad. In this talk we give an overview of the Exterior Section. We will present our members, our main goals, the organized and planned activities, agreements with other scientific associations, and our future action plans. "
        Speaker: Prof. Antonio Picón
        Slides
    • 13:20 15:00
      Lunch break 1h 40m Campus Vida USC

      Campus Vida USC

    • 15:00 20:00
      Nuclear Physics I Aula Química Física (Facultade de Química (USC))

      Aula Química Física

      Facultade de Química (USC)

      • 15:00
        Highlights of the ISOLDE Facility and the HIE-ISOLDE project 25m Aula Química Física

        Aula Química Física

        Facultade de Química (USC)

        The ISOLDE Radioactive Beam Facility is the CERN experiment for the production and acceleration of radioactive nuclei. It is dedicated to the production, study and research of nuclei far from stability. Exotic nuclei of most chemical elements are available for the study of nuclear structure, nuclear astrophysics, fundamental symmetries and atomic physics, as well as for applications in condensed-matter and life sciences. Since more than 15 years it offers the largest variety of post-accelerated radioactive beams in the world today. In order to broaden the scientific opportunities beyond the reach of the present facility, the on-going HIE-ISOLDE (High Intensity and Energy) project will provide major improvements in energy range, beam intensity and beam quality. The first stage has boosted the beam energy of the current REX LINAC to 5.5 MeV/u where the Coulomb excitation cross sections are strongly increased with respect to the previous 3 MeV/u and many transfer reaction channels become available. The second stage of the energy upgrade is being implemented; most of the infrastructure was installed in the winter of 2017, and it will be completed for the start of 2018, allowing energies of the beam up to 10 MeV/u. In this contribution, recent highlights of the ISOLDE facility will be discussed and the HIE-ISOLDE project will be described together with a panorama of the physics cases addressed and a few examples of experiments already realized.
        Speaker: Prof. Maria J. G. Borge (Instituto de Estructura de la Materia, CSIC)
      • 15:25
        Commissioning of the BRIKEN β-delayed neutron detector for the study of exotic neutron-rich nuclei 15m Aula Química Física

        Aula Química Física

        Facultade de Química (USC)

        Beta-delayed neutron emission βn is the dominant decay mode of the most exotic nuclei produced along the path of the rapid neutron capture process. The correct description of the final relative abundances of heavy elements requires a accurate knowledge of delayed neutron emission probabilities Pxn of very neutron-rich nuclei [1]. Our current understanding of this nuclear decay mode lacks of enough experimental data [2]. Furthermore, the Pxn values are sensitive to the nuclear structure, and can be used as test of theoretical models [3]. With these ideas in mind the BRIKEN Collaboration has set up a powerful detection system consisting of: 1) a neutron counter with 148 3 He tubes that has high and constant detection efficiency [4], 2) the high granularity implantation-decay detector AIDA [5], 3) two CLOVER type HPGe detectors. The setup will exploit the high intensity of radioactive beams available at the focal plane of the BigRIPS separator [6] in the RIKEN Nishina Center. The setup received the first radioactive beam of isotopes close to the doubly-magic 78 Ni in Autumn 2016.In this presentation we will report on the first results of this commissioning run, including an evaluation of the performance of the setup. [1] A. Arcones and G. Martinez-Pinedo, Phys. Rev. C 83,045809 (2011) ; [2] R. M. Mumpower et al., Phys. Rev C 94, 064317 (2016); [3] M. Madurga et al., Phys. Rev. Lett. 117, 092502 (2016); [4] A. Tarifeno-Saldivia et al., J. Instrum. 12 (2017) 04006. [5] T. Davinson et al., http://www2.ph.ed.ac.uk/∼td/AIDA/; [6] T. Kubo et al., AIP Conference Proceedings 1224, 492 (2010).
        Speaker: Alvaro Tolosa Delgado (Instituto de Fisica Corpuscular, IFIC (CSIC-UV))
      • 15:40
        Estudio de la estructura de clúster 9Li-4He del núcleo 13B usando el método de dispersión resonante. 15m Aula Química Física

        Aula Química Física

        Facultade de Química (USC)

        El fenómeno de clúster es bastante conocido en física nuclear, de hecho, algunas propiedades de los núcleos pueden describirse asumiendo únicamente algunas interacciones débiles entre dichos clústeres. Dentro de los núcleos ricos en neutrones, los clusteres pueden ser no sólo partículas estables, como la partícula alfa, sino también núcleos deformados y fácilmente polarizables. Este tipo de estructura se denomina estructura de clúster exótica. Dentro de este marco, los cálculos AMD (Antisymmetrized Molecular Dynamics) predicen una estructura del tipo Li-He para los isótopos de B ricos en neutrones. En esta contribución se presenta el primer estudio experimental de los estados de clúster exótico 9Li-4He en el núcleo de 13B usando la técnica de dispersión resonante. La función de excitación obtenida de 13B muestra la presencia de varios picos en una región de energía de excitación nunca antes explorada.
        Speaker: Dr. Juan Pablo Fernandez-Garcia (CNA-University of Seville)
        Slides
      • 15:55
        Gamma and fast-timing spectroscopy around 132Sn from the beta-decay of In isotopes 15m Aula Química Física

        Aula Química Física

        Facultade de Química (USC)

        During the last two decades there has been a substantial effort directed to gather information about the region around the neutron-rich 132Sn [1], the most exotic doubly-magic nucleus presently at reach. Nuclei with a large N/Z ratio in this area of the table of isotopes are of great interest to test nuclear models and provide information about single particle states. Stringent tests of the models can be provided by the reduced electromagnetic transition probabilities connecting nuclear states. In this work we have used fast-timing and gamma spectroscopy to investigate five Sn nuclei, including the doubly magic 132Sn, the two neutron hole 130Sn and two-neutron particle 134Sn, and the one-neutron hole 131Sn and one-neutron particle 133Sn. The Sn isotopes were studied at the ISOLDE facility, where their excited states were populated in the beta-decay of In isomers, produced in a UCx target unit equipped with a neutron converter. The In isomers were ionized using the ISOLDE Resonance Ionization Laser Ion Source (RILIS), which for the first time allowed isomer-selective ionization of indium. The measurements took place at the new ISOLDE Decay Station (IDS), equipped with four highly efficient clover-type Ge detectors, along with a compact fast-timing setup consisting on two LaBr3(Ce) detectors and a fast beta detector. The setup incorporated a tape transport system to remove longer-lived activities. Indium isotopes with masses ranging from 130 to 134 were produced. The RILIS isomer selectivity made it possible to produce odd-mass In isotopes with a clean separation between the 9/2+ and 1⁄2– beta-decaying isomers. For the even isotopes, such as 130In, it was also possible to separate the 5+, 10– and 1– isomers. We report on the lifetime of the 331-keV 1/2+ level in 131Sn, which provides information on the M1 transition to the ground state and on its degree of forbiddeness, similar to what has been recently been measured for 129Sn [2]. We also report on the expanded level scheme of the 131Sn and the preliminary lifetimes of excited states populated in the decay of the 131In (21/2+) isomer. The 132Sn was studied by means of the beta-decay of 132In, and also from the beta-n decay of the 133In 1/2– isomer and the 133In 9/2+ g.s. separately. We present the new level scheme, which have been enlarged with more than 8 new levels and 40 gamma transitions. A crosscheck of previously measured known lifetimes is also provided [3]. References [1] A. Korgul et al, Phys Rev Lett 113,132502(2014) [2] R. Lica et al., Phys Rev C93 044303 (2016) [3] B. Fogelberg et al Phys. Rev. Lett. 73, 2413(1996)
        Speaker: Mr. Jaime Benito García (Grupo de Fisíca Nuclear, Facultad de Ciencias Físicas, Universidad Complutense de Madrid- CEI Moncloa, E-28040 Madrid, Spain)
        Slides
      • 16:10
        Quasi-Free Scattering of Neutron Deficient Exotic Nuclei 15m Aula Química Física

        Aula Química Física

        Facultade de Química (USC)

        Quasi-Free Scattering (QFS) reactions are powerful tool to study to provide information on nuclear single-particle properties. This experimental approach has been extensive in the past to gain information on stable nuclei [1] We have recently extended the method to explore the exotic species. The oxygen isotopic chain brings excellent opportunities covering a very broad range on isospin, raging from weakly bound nuclei, 13O or 24O to stable ones such as 16,17,18O. Previous investigations by L. Atar and P. Fernández [1] in the neutron-rich isotopes (16-24O) proton-induced QFS reactions have been performed. The aim of this work is extending these studies to the proton-deficient area, and investigate (16-13O) nuclear properties. In addition, fragmentation cross sections induced by these nuclei and producing light fragment are relevant in field of charged particle therapy. This technique is advantageous over conventional radiotherapy, thus understanding of these cross sections is important to improve the risk assessment related to this process.
        Speaker: Mr. Juan Manuel Boillos Betete (IGFAE Instituto Gallego de Altas Energías)
        Slides
      • 16:25
        Dissipative effects in fission investigated in complete kinematics measurements 20m Aula Química Física

        Aula Química Física

        Facultade de Química (USC)

        A complete description of the fission process still represents a challenge, despite the recent progress based on time-dependent Hartree-Fock models [1]. Statistical models provide a tool to describe fission probabilities at excitation energies around the fission barrier. This approach is justified because, under such conditions, statistical times dominate over the typical timescales for the coupling between intrinsic and collective degrees of freedom (~10-21s). At high excitation energies, pre- and postscission particle emission and fission probabilities [2,3] indicate that simple statistical approaches are not valid and models, describing the dynamics of the process, are required. These models are based on transport equations, e.g. Fokker-Planck or Langevin, where the main ingredients are the potential landscape and the friction and inertia tensors [4]. The friction parameter is particularly interesting because it quantifies the magnitude of the coupling between collective and intrinsic degrees of freedom in fission. In this work, we propose to investigate these effects by taking advantage of proton-induced fission reactions at relativistic energies for producing highly-excited fissioning nuclei with low angular momentum, where dissipative effects should manifest in a clear way. The SOFIA setup together with the inverse kinematics technique were used for the first time to measure in coincidence the mass and atomic number of the two fission fragments with good resolution [5]. These high-quality data allowed us to obtain new observables in fission. In particular, total and partial fission cross sections and the charge distribution of the fission fragments are used to characterize the fission dynamics at small deformation [6]. Moreover, we will also present the results concerning the neutron excess and the average pre- and postneutron multiplicities, which help us to investigate the postsaddle dynamics [7]. References [1] G. Scamps et al., Phys. Rev. C 91, (2015) 044606 [2] J. P. Lestone et al., Phys. Rev. C 79, (2009) 044611 [3] J. Benlliure et al., Phys. Rev. C 74, (2008) 014609 [4] P. N. Nadtochy et al., Phys. Rev. C 65, (2002) 064615 [5] J. L. Rodríguez-Sánchez et al., Phys. Rev. C 91, (2015) 064616 [6] J. L. Rodríguez-Sánchez et al., Phys. Rev. C 92, (2015) 044612 [7] J. L. Rodríguez-Sánchez et al., Phys. Rev. C 94, (2016) 061601(R)
        Speaker: Mr. Jose Luis Rodriguez Sanchez (USC)
      • 16:45
        Coffee 30m Aula Química Física (Facultade de Química (USC))

        Aula Química Física

        Facultade de Química (USC)

      • 17:15
        A Beyond Mean Field Description of Atomic Nuclei 25m Aula Química Física

        Aula Química Física

        Facultade de Química (USC)

        Traditionally effective interactions like Skyrme, Gogny or relativistic interactions have been used in basic mean field approaches to describe with great success bulk properties of ground states of nuclei, such as masses, quadrupole moments, radii, etc. However, recent developments in beyond mean field calculations, with particle number and angular momentum projection in conjunction with the Generator Coordinate Method (with the deformations $(\beta,\gamma)$, pairing gaps $(\Delta_Z,\Delta_N)$ and angular frequency as generator coordinates) have shown that the Gogny force [1,2] is also able to provide high quality nuclear spectroscopy. This approach has recently been extended to odd-even nuclei [3] allowing thereby to perform isotopic (isotonic) studies of nuclear properties. The strong point of this approach is the ability to simultaneously provide a good description of bulk properties, like binding energies and multipole moments, as well as an accurate and detailed account of excitation energies and transition probabilities. As a validation of the theory in this talk we present a study of the Magnesium isotopic chain. We obtain an outstanding description of the ground-state properties, in particular binding energies, odd-even mass differences, mass radii and electromagnetic moments among others. At the same time a comprehensive study of the spectroscopic properties of $^{25}$Mg is discussed. These studies, together with the spectrum and the transition probabilities of the nuclei $^{42}$Si and $^{44}$S, show that these calculations provide an accuracy comparable with state-of-the-art shell model calculations with tuned interactions. The advantages of the present approach as compared to the shell-model one are the added value of the intrinsic system interpretation and that the interaction, the Gogny force, is well known for its predictive power and good performance for bulk properties all over the chart of nuclides. \vspace{1cm} 1.- M. Borrajo, T. R. Rodriguez and J. L. Egido, Phys. Lett. B 746 (2015) 341-346 2.- J. L. Egido, M. Borrajo and T. R. Rodriguez, Phys. Rev. Lett. 116 (2016) 052502. 3.- M. Borrajo and J. L. Egido, Phys. Lett. B 764 (2017) 328–334
        Speaker: Prof. J. Luis Egido Egido (Universidad Autónoma de Madrid)
        Slides
      • 17:40
        Exploiting electron parity violation: from Standard Model tests to dark matter detection predictions 15m Aula Química Física

        Aula Química Física

        Facultade de Química (USC)

        There has been recent interest in low energy, high luminosity polarized electron beams for studies of parity-violating electron scattering, such as the MESA accelerator at Mainz or an upgraded FEL facility at Jefferson Lab. Accurate measurements of the parity-violating asymmetry in elastic electron scattering from nuclei can be used to determine Standard Model couplings, such as the weak-mixing angle, or higher-order radiative corrections, as well as to extract specific information on the nuclear and nucleon structure. To this end, low uncertainties are required from modeling some confounding nucleon and nuclear structure effects, including isospin mixing, nucleon strangeness content or Coulomb distortion. We estimate the sizes and theoretical uncertainties of such effects for a proton and a carbon 12 targets. An experimental precision in the asymmetry of a few tenths of a percent may be reachable under certain kinematic conditions, that are also discussed here for the same nuclear target. This high precision parity-violating asymmetry in elastic electron scattering can also be used to relate in a very simple manner the elastic electron-nucleus scattering cross section with the elastic weak-neutral neutrino-nucleus cross section for even-even targets or, more generally, for any target in coherent scattering. This novel relationship allows us to exploit experimentally well-determined quantities (related to electron-nucleus scattering) to predict as-yet unknown observables (weak neutral neutrino-nucleus cross sections). This idea is simply extended to link electron scattering to an even more uncertain magnitude: the detection rate of weak-interacting massive particles, that are dark matter candidates.
        Speaker: Dr. Oscar Moreno (Universidad Complutense de Madrid)
        Slides
      • 17:55
        Proton-neutron pairing studied with transfer reactions 15m Aula Química Física

        Aula Química Física

        Facultade de Química (USC)

        Pairing correlations in nuclei is one of the most active fields in Nuclear Physics. It is crucial for understanding different processes and characteristics of nuclei such us superfluidity. We can easily found clear situations where neutrons form strongly correlated pairs with total angular momentum J=0 and isospin T=1. This produces a strong enhancement of two-neutron transfer reactions, thus being the main probe to test correlations. In N=Z nuclei one would expect to observe also a strong correlation between neutrons and protons. Here, we can find isovector pairs with J=0; T=1 but also isoscalar ones with J=1; T=0. However, the existence and magnitude of pn isoscalar pairing is still under debate. Many experiments on np transfer have been made along the N=Z line but very few performed and analyzed systematically along a major shell. In this contribution, we analyze (p,3He) and (3He,p) transfer reactions in N=Z sd-shell nuclei. The exclusive cross sections to the lowest 0+ and 1+ states in the odd-odd N=Z nuclei were populated in a series of experiments performed at Grand Raiden high-resolution spectrometer at the RCNP of the Osaka University. These data will be compared to 2nd-order DWBA calculations with proton-neutron amplitudes obtained in the Shell Model formalism by using USDB interaction. The preliminary analysis shows tentative cases where the pn isoscalar pairing is not negligible and need to be taken into account in order to reproduce the present experimental data.
        Speaker: Mr. Lay Valera José Antonio (Universidad de Sevilla)
        Slides
      • 18:10
        Symmetry energy and the neutron star core-crust transition with Gogny forces 15m Aula Química Física

        Aula Química Física

        Facultade de Química (USC)

        An accurate determination of the core-crust transition is necessary in the modelling of neutron stars for astrophysical purposes. The properties of the transition are intimately related to the isospin dependence of the nuclear forces at low baryon densities. Finite-range Gogny nuclear interactions are widely used in nuclear structure calculations but there are fewer studies of neutron stars with these interactions. In this work, we investigate the core-crust transition in neutron stars using several Gogny forces and analyse the deduced crustal thickness and crustal moment of inertia of the star. In a first stage, we calculate the second-, fourth- and sixth-order coefficients of the Taylor expansion of the energy per particle of asymmetric nuclear matter in powers of the isospín asymmetry for Gogny forces. These coefficients provide information about the departure of the symmetry energy from the widely used parabolic law and can influence significantly the results for the location of the inner Edge of neutron star crusts. Next, we evaluate the neutron star core-crust transition density by looking at the onset of thermodynamical instability of the liquid core. The analysed Gogny forces predict the ranges 0.094 fm-3 ≤ ρt ≤ 0.118 fm-3 for the transition density and 0.339 MeV fm-3 ≤ Pt ≤ 0.665 MeV fm-3 for the transition pressure. The transition densities of the Gogny forces show an anticorrelation with the slope parameter L of the symmetry energy, whereas the transition pressures are not found to correlate with L. Finally, the fraction of the mass and moment of inertia of the neutron star that reside in the crust are evaluated using the forces that provide stable solutions of the Tolman-Oppenheimer-Volkov equations.
        Speaker: Ms. Claudia Gonzalez-Boquera (Universitat de Barcelona)
        Slides
      • 18:25
        Evidencia experimental de caos en los estados ligados del 208Pb 15m Aula Química Física

        Aula Química Física

        Facultade de Química (USC)

        En este trabajo se analiza el espectro del núcleo de 208Pb usando los datos experimentales recientemente obtenidos por Heusler et al. en el Maier-Leibnitz Laboratorium de Garching (Alemania). Han sido identificados los 151 estados más bajos y esto constituye el mayor conjunto de datos experimentales de estados ligados de un núcleo disponible a día de hoy para un estudio estadístico del caos cuántico. Como resultado del análisis obtenemos un comportamiento claramente caótico para los estados de paridad natural y un comportamiento intermedio entre caos y regularidad para los estados de paridad no natural. Esta diferencia puede explicarse en base a la intensidad de la interacción residual, resultado que constituye una confirmación basada en datos experimentales de la conocida predicción del modelo de capas de que es la interacción residual la responsable de introducir el caos en el núcleo cuando es lo suficientemente intensa para destruir el movimiento regular debido al campo medio.
        Speaker: Dr. Laura Muñoz (Grupo de Física Nuclear, Facultad de Ciencias Físicas, Universidad Complutense de Madrid)
        Slides
      • 18:40
        Transfer to the continuum calculations of (p, pn) and (p, 2p) reactions at intermediate and high energies. Application to Borromean nuclei. 15m Aula Química Física

        Aula Química Física

        Facultade de Química (USC)

        Nucleon removal (p,pn) and (p,2p) reactions at intermediate energies have gained renewed attention in recent years as a tool to extract information from exotic nuclei, thanks to the availability of exotic beams with which to perform these reactions in inverse kinematics. These reactions explore the single-particle structure of the projectile nucleus and are complementary to nucleon removal experiments with heavier targets (knockout), due to their enhanced sensitivity to the nuclear interior. Of special interest is their application to Borromean nuclei, three-body systems whose two-body subsystems are all unbound, since their exotic nature makes their structure a topic of current interest.
        Speaker: Mr. Mario Gómez Ramos (Universidad de Sevilla)
        Slides
      • 18:55
        Parity violating electron scattering 20m Aula Química Física

        Aula Química Física

        Facultade de Química (USC)

        Nucleons are not point like particles, they are made of quarks interacting each other by exchanging gluons. Gluons can be converted into quark-antiquark pairs giving raise to the sea quark. Quantum Chromodynamics (QCD) is the fundamental theory that describes the strong interaction; however, due to the complexity of the quark-gluon dynamics, QCD does not allow us to get analytical results in the energy region of interest to Nuclear Physics at low 4-momentum transfer, $Q^2$. Alternatively, the internal dynamics of the quarks inside the nucleon can be described in terms of several phenomenological functions (form factors) which depend on a single scalar variable: $Q^2$. The form factors are related to the electric, magnetic, axial and axial-vector charge distributions in the nucleon. The study and determination of these nucleon form factors can provide constraints to the microscopic models that aim to describe the nucleonic structure from QCD. Moreover, form factors are a main ingredient for the description of the lepton-nucleus/nucleon cross sections. One of the main objectives of our work is to improve the current knowledge on the structure of the nucleon through the study of the form factors. As tools, we have analyzed elastic electron-nucleon and quasielastic electron-nucleus scattering processes. These reactions provide information on the electromagnetic (EM) and weak neutral current (WNC) form factors. Although the EM interaction is dominant in electron-nucleon/nucleus scattering, i.e., parity conserving processes, the electron also feels the weak (neutral) interaction that does not conserve parity. Due to the strength of the weak interaction (several orders of magnitude lower than the electromagnetic one) to get information on the weak interaction is essential to analyze observables whose presence is due unequivocally to parity violating processes. Thus, we have studied the observable called parity violating asymmetry (${\cal A}^{PV}$) defined as ${\cal A}^{PV}=(\sigma^+ - \sigma^-)/(\sigma^+ + \sigma^-)$, where $\sigma^{+/-}$ represents the differential cross section (electron-proton or electron-nucleus) with positive/negative helicity of the incident electron. The PV asymmetry linked to the elastic electron-proton scattering (PVep asymmetry), $p(\vec{e},e')p$, is particularly sensitive to the electric and magnetic strange contributions. An statistical analysis of all PVep asymmetry data has also been presented. From this analysis we have got the highest precision constraint for the vector strange form factor compatible with the experimental data up to date. We have also presented a general study of the PV asymmetry associated to quasielastic electron-nucleus scattering processes (PVQE asymmetry). From our analyses we conclude that the PVQE asymmetry is an excellent observable to obtain nucleonic information on the axial-vector sector of the weak neutral current. Specifically, measurements of the PVQE asymmetry at backward scattering angles would provide information on the radiative corrections entering in the isovector axial-vector sector.
        Speaker: Dr. Raul Gonzalez Jimenez (Ghent University)
        Slides
      • 19:15
        The Laser Laboratory for Acceleration and Applications 15m Aula Química Física

        Aula Química Física

        Facultade de Química (USC)

        The development of high power laser systems based on the Chirped Pulse Amplification (CPA) technique [1] has lead to the advancement of the so called laser driven plasma accelerators. By focusing an ultra-intense ultra-short laser pulse in a target material, it is possible to produce accelerating gradients above 10 GeV/m, which are some 3 to 4 orders of magnitude larger than the values reached using conventional accelerators based on radiofrequency cavities. This achievement has generated during the last decade an intense research activity leading to the discovery of the physical mechanisms that can be used to produce high energy beams of electrons, ions or photons with unprecedented characteristics [2]. The Laser Laboratory for Acceleration and Applications (L2A2) at the University of Santiago de Compostela in Spain is a new infrastructure for the investigation of laser-plasma particle acceleration and the use of this new technology in several fields of application. In particular, L2A2 will focus its initial research program in developing alternative technologies for the production of medical radiotracers using laser-plasma accelerated beams of protons and light ions. Another field of interest is advanced tomographic techniques using laser-plasma generated X-rays.
        Speaker: Dr. Jose Benlliure (University of Santiago de Compostela)
      • 19:30
        POSTERS 30m Aula Física (Santiago de Compostela, Facultade de Química)

        Aula Física

        Santiago de Compostela, Facultade de Química

    • 15:15 19:05
      27º Encuentro Ibérico de Enseñanza de la Física I Aula de Biología (Facultad Química (USC))

      Aula de Biología

      Facultad Química (USC)

      • 15:15
        Experimentos para la formación de profesores 1h 15m
        Experimentos para la formación de profesores
        Speaker: Prof. Benito Vázquez (Universidad de Vigo)
      • 16:30
        Proyectos de innovación en la enseñanza de la Física 30m
        Proyectos de Innovación en la enseñanza de Física
        Speaker: Prof. José Viñas
      • 17:00
        Coffee break 30m
      • 17:30
        Introducción del programa de simulación de circuitos eléctricos PSpice en el laboratorio de Física General 15m
        Este trabajo, basado en un proyecto de innovación docente desarrollado con estudiantes de diferentes grados de la rama de ingeniería industrial, describe las líneas básicas que permiten introducir los programas de simulación de circuitos eléctricos en el laboratorio de física general. Se seleccionan varias prácticas de laboratorio basadas en análisis de circuitos de corriente continua, análisis transitorios y análisis de circuitos de corriente alterna, y se muestran ejemplos de cómo profesores y estudiantes pueden usar los programas de simulación para hacer actividades simples asociadas con los propios ejercicios de laboratorio o con tópicos relacionados.
        Speaker: Dr. Antonio Angel Moya (Universidad de Jaén)
      • 17:45
        Caracterización de oscilaciones forzadas mediante el sensor de aceleración de un smartphone 15m
        En este trabajo en concreto, presentamos una nueva metodología con la que se pretende orientar el aprendizaje como una tarea de indagación que favorezca la participación de los estudiantes en la construcción de los conocimientos. Para lograr lo anterior, se propone hacer hincapié en la necesidad de enseñar a buscar respuestas a través del análisis, la observación y la experimentación. Una forma de llamar el interés de los alumnos es a través de aparatos electrónicos, y qué mejor que un Smartphone. En particular, se aborda el estudio de las oscilaciones forzadas (una experiencia clásica de laboratorio) mediante el sensor de aceleración de un Smartphone. El dispositivo experimental implementado consta de un Smartphone ubicado en una deslizadera sobre un carril de aire. La deslizadera se une mediante un resorte a un motor vibrador. Reduciendo el caudal de aire, conseguimos un amortiguado en las oscilaciones como consecuencia de la fricción entre la deslizadera y el carril. Los datos obtenidos a partir del acelerómetro, mediante una aplicación gratuita, se pueden exportar fácilmente a un ordenador y se ajustan a la ecuación que gobierna la aceleración en un movimiento oscilatorio amortiguado débil y forzado. Se han obtenido discrepancias entre la pulsación, Ω, teórica y la experimental, calculada a través del ajuste, de tan solo un 0,4%.
        Speaker: Mrs. Isabel Salinas Marín (Departamento de Física Aplicada, Universitàt Politècnica de València)
      • 18:00
        Adquisición de competencias transversales mediante laboratorios virtuales 15m
        Los laboratorios virtuales son una herramienta que facilita la adquisición de conceptos y su comprensión, poniendo el foco en el aprendizaje activo, y permitiendo el control de las variables de un proceso para analizar las variables subyacentes. En los últimos años hemos realizado en Java un buen número de estos laboratorios, muy bien acogidos por los alumnos, que los han utilizado tanto en prácticas de aula y de laboratorio, como en su estudio personal. Sin embargo, la actual evolución de los principales navegadores de Internet nos ha llevado a ir abandonando el uso de Java, y utilizar HTML5 y JavaScript. Además, este paso permite extender el uso de los laboratorios a los dispositivos móviles, lo que añade además la posibilidad del control por medio de la pantalla táctil. Las encuestas y el análisis de resultados en grupos de control han permitido comprobar la mayor satisfacción y motivación de los estudiantes, y su reflejo en las calificaciones en los aspectos tratados. Además, suponen un apoyo importante en el desarrollo de competencias transversales como la comprensión e integración de conceptos, análisis y resolución de problemas, y pensamiento crítico.
        Speaker: Dr. Marcos H. Giménez Valentín (Universitat Politècnica de València)
      • 18:15
        Formación en metodologías activas a través de proyectos europeos en el Master del Profesorado 15m
        Una de las dificultades que frecuentemente encuentran los estudiantes del Master del Profesorado está relacionada con la puesta en práctica de los contenidos teóricos que recibe durante su formación. Presentamos en este artículo una experiencia realizada en el Máster Universitario en Profesor de Educación Secundaria Obligatoria y Bachillerato, Formación Profesional y Enseñanza de Idiomas, de la Universidad de Burgos, en las especialidades de Física y Química durante el curso académico 2016-2017. El diseño de las actividades permitió la formación en metodologías docentes activas en las que el estudiante de Máster toma alternativamente el rol de profesor-alumno. Se describen brevemente dos actividades basadas en sendos proyectos europeos: una actividad en torno al aprendizaje por indagación y una segunda relativa a la resolución de problemas.
        Speaker: Dr. Miguel Angel Queiruga Dios (Colegio Jesús-María. Universidad de Burgos)
      • 18:30
        TRATANDO DE DESMONTAR LA ARTIFICIAL BARRERA ENTRE FÍSICA Y BIOLOGÍA EN LA FORMACIÓN DE FUTUROS BIÓLOGOS. Lecciones de una experiencia (2010-2015) en un Grado en Biología. 15m
        ¿Cuál debería ser el principal objetivo de la Física incluida en el plan de estudios de todos los grados (españoles) en Biología?, ¿cómo debería diseñarse e impartirse la asignatura para lograr ese objetivo? Un equipo de profesores (físicos) y de estudiantes de posgrado (biólogos) y de grado (futuros biólogos), constituido ad hoc para reflexionar sobre el papel de la física en la formación de los biólogos del siglo XXI, ha tratado de dar respuesta a esas (y a otras) preguntas. Sus primeras conclusiones han sido recientemente publicadas, simultáneamente, en las revistas de las sociedades científicas españolas de Física (RSEF) y de Bioquímica y Biología Molecular (SEBBM) [1]. Pero ¿es posible lograr ese objetivo en un cuatrimestre? En la publicación citada se afirma que el análisis de la experiencia de la asignatura Física en el Grado de Biología Sanitaria de la Universidad de Alcalá a lo largo de cinco cursos (2010-2011 a 2014-2015) permite concluir que la mayoría de los alumnos lo logró, a pesar de que solamente un pequeño porcentaje de ellos (≈20%) había cursado Física en 2º de bachillerato; y que ese objetivo se puede alcanzar (en un cuatrimestre) si el alumno tiene el suficiente estímulo y el profesor muestra un interés claro por la Biología. Tratamos aquí de justificar dicha conclusión, de forma resumida.
        Speaker: Dr. del Romero Guerrero Armando (Universidad de Alcalá, España)
      • 18:45
        16 experimentos de física que comparan el proceso real con una simulación 15m
        Introducción Modellus [1] es un programa informático de libre disposición con el que los profesores podemos crear con bastante facilidad simulaciones de fenómenos variados. Estas simulaciones pueden versar sobre contenidos relevantes del currículum de Física en Secundaria y en Bachillerato [2]. En este sentido, una posibilidad muy interesante, pero de momento poco explotada, es la de realizar experimentos, en los que se estudie la concordancia entre el fenómeno físico investigado y una simulación del mismo, creada por el docente o por los propios alumnos con este programa. Se trata de un recurso muy útil para el análisis experimental y no sólo puede complementar muy bien a otros recursos (por ejemplo, el uso de sensores de magnitudes), sino que, en algunas ocasiones, puede salir en auxilio del investigador, cuando aquellos no son utilizables. Listado resumido de experimentos Hemos realizado, hasta el momento, 16 experimentos (y sus variantes) de física, que llevaron a cabo grupos de estudiantes de varios institutos. Todos ellos están disponibles en Internet [3], donde se accede a una descripción de cada uno y se pueden descargar las animaciones resultantes tras los análisis experimentales. En la tabla nos referimos escuetamente a 9 de ellos. (La tabla con los 16 experimentos comentados puede verse en el documento que se adjunta) Comentarios sobre dos de los experimentos En la ponencia mostraremos varios análisis experimentales con cierto detalle, manipulando las correspondientes simulaciones. Veamos aquí un breve comentario sobre dos de ellos. Tiro oblicuo: Ejemplo de movimiento, cuyas posiciones no se pueden medir con el sensor. Para crear la animación (Fig. 1) usamos una filmación sobre un tiro libre en un partido de baloncesto. El análisis experimental permite verificar, en primer lugar, la hipótesis de Galileo de descomposición del movimiento oblicuo de la pelota en un movimiento horizontal (uniforme) y otro vertical (uniformemente acelerado). Los alumnos le imponen a la pelotita virtual que cumpla las leyes escritas bajo dicha hipótesis, y comprueban que se sitúa en todo instante sobre la pelota real. Usando los valores conocidos de las dimensiones de la cancha de baloncesto, los alumnos también traducen las ecuaciones de pixels a m y así verifican que la aceleración vertical de la pelota es igual a g. (La figura 1 puede verse en el documento que se adjunta) Rodadura por un plano horizontal: Ejemplo de experimento “doble”, en el que primero se usan sensores de magnitudes y luego se utiliza el simulador (cuando los alumnos toman medidas del movimiento con el sensor de posición también lo filman). El primer análisis realizado con el software de los sensores permite obtener tablas y gráficas sobre la evolución de las magnitudes cinemáticas (posición, velocidad y aceleración), y deducir a partir de estos datos otras magnitudes, como la fuerza de rozamiento por rodadura que va frenando al carrito hasta detenerlo. En la segunda parte del experimento, se construye una animación Modellus, sobre la que se vuelca el clip de video del movimiento, para compararlo con una simulación del mismo que obedece a las leyes de Newton. La animación resultante (Fig. 2) permite verificar no sólo la aplicación de dichas leyes al propio movimiento (una vez hecho el cambio de escala, la partícula virtual queda siempre sobre el punto central del carrito filmado), sino también a sus gráficas (las gráficas del movimiento virtual también se van dibujando exactamente encima de las obtenidas con los sensores) (La Figura 2 puede verse en el documento que se adjunta) Conclusiones La comparación entre el proceso real y una simulación del mismo que obedece las leyes de la Física es una técnica potente y, a la vez, bastante sencilla para la realización de algunos experimentos en el Instituto. Los 16 experimentos que hemos desarrollado hasta ahora se han podido incardinar en los currículos de Física en Secundaria y en Bachillerato, y también se han difundido con muy buena acogida en cursos de formación docente. Referencias [1] http://modellus.co/index.php?lang=es [2] M. Alonso. Revista Española de Física, 22, (2008) 3, 52. [3] http://www.iesleonardoalacant.es/Departamento-fisica/Experimentos-Modellus/Experimentos-modellus.htm
        Speaker: Dr. MANUEL FRANCISCO ALONSO SÁNCHEZ (IES "LEONARDO DA VINCI" DE ALICANTE)
    • 15:15 19:15
      Energy and Sustainability I Aula de Física (Facultad Química (USC))

      Aula de Física

      Facultad Química (USC)

      • 15:15
        Present state of the power system in Spain and the optimal development of a future variable renewable energy (VRES) mix 30m
        As the percentage of electricity from variable renewable energies, (wind and solar) gets above some 30-40% of the mix, the problems of integrating the VRES supply into the distribution grid rise significantly. In fact, the characteristic intermittency of renewable sources necessarily demands for its effective integration some combination of efficient and flexible backup plants, large energy storage systems, smart grids, etc. and, consequently, the costs of electricity could be notably increased. This article analyses the present situation of the power mix making use of the latest data available from the Spanish distribution grid regulator (Red Eléctrica Española). The study is carried out in a two-tier analysis: Firstly we perform a descriptive analysis of the latest trends comparing the generation of the last years. Secondly, based mainly on the European directions on the future limitations of CO2 emissions, we make an analysis of the deployment of the optimal mix of VRES that would minimize the both the need of backup from conventional sources, as well as surpluses. A reduction in fossil fuel generation, as recommended by the European Union (EU) and several international treaties, is also considered. As far as we know, this kind of studies, based on linear programming for establishing the optimal power generation mixes for VRES at a country level, are unusual and yet to come. However, they can provide key figures to policymakers for the establishment of desirable investments for renewable energies in the nearly future. Evidently, the main difficulty of the above study is caused by the large unpredictability of wind and solar resources and for this reason we base our optimization technique on the hourly data series (8760 hours in one year) provided by REE. It is also interesting to point out that in finding the optimal mix for VRES, we have considered two components for solar: photovoltaics (PV) and concentrating solar power (CSP). Practically, none of the European scenarios take into account these two solar components since it is known that for latitudes higher than the one of Spain, the conversion efficiency of CSP diminishes very rapidly. In this work we have studied three possible scenarios. In the first one we suppose the hypothetical case of the total demand being mostly supplied by variable renewable energies. In this case, it is assumed that all the electricity demand is covered by wind and solar energies (PV and CSP). To do so in the solution of the problem we apply the stringent condition that the resulting mix should be optimal, that is, that the 8760 hourly periods in the year of backup and surplus are simultaneously minimized. The solution of the problem gives, as expected that the increase in VRES needed is too large to be implemented before 2030. In addition the amounts of surplus and backup are also unmanageable without an efficient storage and lack of demand-side response technologies. In the second case we suppose that the hydraulic and nuclear generation are maintain ned at their present levels. Therefore, the VRES should cover only the reduced demand, that is, the difference between the total demand minus the sum of the hydraulic and nuclear components for each of the hours of the year. Under this situation, the solution of the optimization problem yields that the present wind, solar-PV and solar-CSP generations would have to be increased by 97%, 20%, and 528%, respectively. In this case, we have also calculated the aggregated yearly backup needed and the surplus obtaining 14.2 and 5.7 TWh, respectively. It is also evident that without storage the surplus electricity would be lost. In the third scenario we study the more realistic case that Spain will follow the targets assigned by the EU for the reduction of emissions in 2030 as well as the increase of the corresponding renewable energies. This implies a drastic reduction in the future coal-generated electricity reaching 15.2 TWh by 2030 (about 30% of its present amount). We call this case, the European Union-2030 Scenario. After performing the corresponding operations for the optimization problem, as in the previous case, we find that the current wind, PV and CSP generations would have to be augmented by 64%, 27%, and 332%, respectively. In addition, the yearly backup and surplus have been drastically reduced to 2.9 and 3.3 TWh, respectively. We would like to remark that it might appear surprising the large percentages resulting for CSP which can be explained by its low present participation in the actual generation mix and above all by its possibility of evening and overnight storing of energy during several hours after sunset. It is important to remark that the needed backup will be mainly supplied by natural gas plants, which are less contaminating and have a faster response than coal plants. Finally, in this communication, we also discuss other strategies that will have to be implemented if we want to handle large amounts of VRES. These are storage, demand-side management, distributed generation, and smart grids, since they contribute to the improvement of the so-called flexibility of the systems for power generation. With respect to the management of the surplus, evidently storage could in theory accumulate the corresponding energy for later use, thus partially substituting the backup systems. However, a massive use of storage still has to wait due to the high cost of batteries and the need of a practical seasonal storage (summer-to-winter in the case of solar) yet to be developed. Acknowledgments The authors would like to acknowledge the support given by the Spanish Royal Physics Society (RSEF) and Red Eléctrica Española (REE) for the realization of this work. We also acknowledge the fruitful technical discussions maintained with Enrique Soria and Javier Domínguez from the Renewable Energy Department of CIEMAT.
        Speaker: Dr. Roberto Gómez-Calvet (Universidad Europea de Valencia)
      • 15:45
        Planta de biogás de un matadero de aves. Un ejemplo de economía verde. 30m
        Los mataderos de aves generan efluentes líquidos compuestos de grasas, proteínas y restos de animales. También generan desechos sólidos, tales como huesos, patas, cabezas, piel y otros restos de carcasas. Normalmente, estos desechos no son utilizados por las empresas y a menudo son enviados a vertederos o destinados para la producción de compost, que, en el caso de los residuos avícolas, poseen un alto contenido en nitrógeno teniendo un impacto medioambiental negativo. Si se tratan mediante digestión anaerobia (DA), se consigue, por una parte, disminuir muchísimo el impacto ambiental con respecto al causado por su vertido directo al medioambiente, y, por otra parte, generar biogás, que es una fuente de energía renovable capaz de suplir las necesidades de calor de la propia industria cárnica. En este trabajo se propone la construcción de una planta de DA anexa a un matadero de aves. La planta se alimenta con los residuos generados por dicho matadero y el biogás obtenido se quema en calderas para proporcionar calor de proceso, que es consumido por la propia industria (autoconsumo). Este proyecto pretende ser un ejemplo de generación distribuida y de economía verde.
        Speaker: Dr. Francisco Cuadros Blázquez (Facultad de Ciencas. Departamento de Física Aplicada.Universidad de Extremadura)
      • 16:15
        Centrales termosolares Brayton híbridas: predicción termodinámica de eficiencias anuales y emisiones 30m
        En este trabajo se realiza una simulación válida para plantas termosolares híbridas, de ciclo Brayton y de torre de concentración, desde un punto de vista termodinámico. Con este tipo de plantas de generación de energía eléctrica se pretende reducir el consumo de combustibles y la emisión de contaminantes, así como conseguir una potencia neta de salida estable. Estas plantas híbridas emplean dos fuentes principales de energía para su funcionamiento: la energía termosolar, proveniente de un campo de heliostatos que recoge y concentra la radiación solar recibida dirigiéndola hacia un colector solar y la energía que se origina en la oxidación de combustibles fósiles dentro de una cámara de combustión. La simulación incluye las principales pérdidas de energía que se producen en los diferentes subsistemas que componen la planta. Se presentan predicciones anuales para las eficiencias de la planta así como datos de consumo de combustible sobre la base de gas natural y emisiones. Los resultados numéricos se han obtenido con condiciones meteorológicas reales y sobre las dimensiones de una planta real de aproximadamente 4.5 MW.
        Speaker: Ms. Rosa Merchán (University of Salamanca)
      • 16:45
        Coffee Break 30m
      • 17:15
        Caracterización térmica de muros en condiciones dinámicas utilizando termografías 30m
        Actualmente, la mejora de la eficiencia energética es uno de los pilares del desarrollo sostenible. Una parte importante de la mejora de la eficiencia energética se centra en la reducción del consumo energético de los edificios, lo cual hace necesario desarrollar métodos de caracterización térmica de sus componentes, tales como los muros. Con este objetivo, se ha desarrollado un experimento en condiciones dinámicas que permita estimar la resistencia y la capacidad térmica de diferentes muros, ya sean homogéneos o heterogéneos. En este experimento se ha construido una caja cuasi-adiabática en la que el muro a analizar se ubica en una de sus caras. En esta caja se procede a generar una excitación térmica de dicho muro mediante una exposición controlada a radiación generada por lámparas incandescentes. Esta radiación incide sobre sus superficies interior y exterior, y provoca variaciones temporales de las temperaturas en el interior y el exterior de la caja. Esta variación temporal en las temperaturas de las superficies del muro a analizar va a ser medidas en diferentes instantes de tiempo mediante la obtención de termografías. La utilización de temperaturas de superficie medidas utilizando termografías supone una innovación respecto al tradicional uso de medidas de flujo de calor realizadas con fluxómetros. Al tratarse de un experimento en condiciones dinámicas donde la utilización de fluxómetros está limitada teóricamente resulta útil estudiar el uso de termografías. La limitación del uso de fluxómetros se debe a que sus medidas producen una amplificación de las altas frecuencias que pueden estar presentes en las señales de excitación del muro, siendo dicha amplificación contradictoria con las observaciones físicas. En el presente trabajo se ha utilizado un modelo físico en forma de circuito térmico para representar el balance de energía que atraviesa el muro para determinar su resistencia y su capacidad térmicas. El modelo utiliza como variables independientes las temperaturas ambiente y la irradiancia, y como variables independientes las temperaturas de superficie. El procedimiento puede ser validado registrando un número significativo de series temporales que permita obtener los valores de la resistencia y capacidad térmicas junto a una medida de su incertidumbre. Y una vez obtenidos estos valores de forma experimental, se puede proceder a su comparación con los valores nominales especificados por el fabricante para la resistencia y capacidad térmica del muro analizado.
        Speaker: Prof. Diego-Pablo Ruiz Padillo (Universidad de Granada)
      • 17:45
        Optimal spatial distribution of solar and wind power plants over the Iberian Peninsula and complementary energy systems 30m
        The introduction of massive renewable power in the energy system of a country needs to be treated carefully. Renewable energies (RE) such as solar and wind have an strong dependence on the meteorological conditions. This leads to a large temporal variance. Therefore there should be some other complementary systems to fit the energy production (EP) to the demand (ED). It is a challenge try to minimize the costs associated to the growth of renewable power systems. In this work we propose different possibilities to face this problem. The first approach consists of distributing solar and wind farms in a smart way, trying not only to get maximum capacity factor, but to minimize the temporal variance of the production respect to the energy demand. This problem has been already presented for the Iberian Peninsula at monthly time scales [1]. In this work we applied the same methodology at daily time scale. The method is applied to a database of solar and wind power potential generation constructed from the outputs of regional climate models runs (hindcast data) with a spatial resolution of 10km over the Iberian Peninsula. The quality of this data has been extensively proved [2] In spite of the strong reduction of the variance by applying this methodology, there still exists importat differences respect the energy demand . When RE is larger that ED the energy should be stored. In this work we only deal with pumped-storage hydroelectricity. The most storage we need the higher the associated costs will be. On the other hand if storage is insufficient some energy will be lost. When RE is smaller other systems should be switch on. If there is energy stored previously this should be used. If not, we need some extra energy power systems. Therefore it is necessary to reach a compromise between our RE installed power, pumped-storage capacity and extra systems in order to minimize the costs assciated. In this work we present an study of the configuration that the whole power system (electricity) should have in order to minimize costs and maximize the use of RE. This estimation has been obtained for the current (mean of last 5 years) ED in Spain and Portugal.
        Speaker: Dr. Juan Pedro Montavez (Departamento de Física, Universidad de Murcia)
      • 18:15
        Impact of Future High-Variable Renewable Energy Mixes on 2030 Sustainability and Climate Change Goals 30m
        This paper examines the present situation and evolution of the power mix and greenhouse gas emissions at global level to meet Sustainable Development Goals (SDGs) with a holistic model. We have performed a descriptive analysis of the latest trends. Based mainly on selected scenarios of high-VRES, to achieve desired targets, using a holistic model approach, our results identify the feasibility of selected target goals by 2030 at global and regional level. Results can provide key findings that policymakers, governments, and energy industries could benefit to achieve desirable Sustainability Development Goals.
        Speaker: Dr. Silvia Serrano (Universidad Politécnica de Madrid)
      • 18:45
        Generando hidrógeno con agua y luz: Trisulfuros ternarios bidimensionales en celdas fotoelectroquímicas 30m
        Desde 1972 cuando Fujishima y Honda[1] demostraron que la ruptura de la molécula de agua con luz y TiO2 como fotoánodo era posible, el interés por investigar compuestos capaces de generar de hidrógeno mediante la disociación de H2O en celdas fotoelectroquímicas (PECs) ha ido aumentando notablemente y con una mayor intensidad en los últimos años[2,3]. Particularmente, destacan las investigaciones con materiales pertenecientes a la familia de los calcogenuros de metales en transición (TMCs por sus siglas en inglés), entre los cuales se encuentran el grupo de los trisulfuros metálicos binarios (MS3), investigados previamente como fotoánodos en procesos de generación de H2[4,5], y el de trisulfuros metálicos ternarios (MM’S3, M y M’= Ti, Zr, Hf, Nb, Ta, etc.), investigados en el presente trabajo. Estos materiales exhiben propiedades que cumplen los requerimientos necesarios para ser utilizados en procesos de fotogeneración de hidrógeno en PEC, i.e., morfología bidimensional que les confiere una alta superficie específica, idónea energía de la banda prohibida, propiedades de transporte óptimas, adecuada posición de sus bandas de energía[6], en la interfase semiconductor/electrolito, etc. Los materiales investigados en este trabajo (TixNb1-xS3 y TixZr1-xS3) se han sintetizado a partir de bicapas metálicas de Ti-Nb y Ti-Zr mediante una reacción sólido-gas entre dichas bicapas y azufre en el interior de una ampolla sellada a vacío y calentada a 550ºC. Las muestras obtenidas se han caracterizado estructuralmente por difracción de rayos X (XRD), composicionalmente por análisis de energía dispersiva de rayos X (EDX) y espectroscopia Raman y, finalmente, morfológicamente mediante microscopía electrónica de barrido (SEM, SEM-FEG) y microscopía electrónica de transmisión (TEM). La caracterización electroquímica para estudiar la interfase semiconductor/electrolito se realizó utilizando una celda fotoelectroquímica en configuración de 3 electrodos, siendo el platino (Pt) el contraelectrodo (CE), los materiales investigados los electrodos de trabajo (WE) y un electrodo de Ag/AgCl como referencia. Como electrolito se ha usado NaSO3 0.5M . Figura 1. Morfología del trisulfuro ternario de Ti-Zr sintetizado a 550ºC durante 20h. Como resultado, se ha obtenido por primera vez la posición de los niveles de energía respecto al electrodo normal de hidrógeno (NHE) a partir de los potenciales de banda plana y la energía de banda prohibida, comprobando que dichos materiales son idóneos para la generación de hidrógeno asistida por luz. La fotogeneración de H2 en PEC se realizó con 200mW/cm2 de iluminación (luz blanca) a dos potenciales de polarización 0.0V y 0.3V vs Ag/AgCl. Se han obtenido flujos de hidrógeno de hasta ~140 μmolH_2/h, cuantificados mediante un espectrómetro de masas. Estos valores se compararán con aquellos obtenidos con otros materiales bien establecidos y se discutirán nuevas aproximaciones para mejorar estos compuestos. Los autores agradecen a F. Moreno el apoyo técnico prestado y al proyecto MINECO-FEDER (2015-65203R) la financiación económica. E. Flores agradece al Consejo Nacional de Ciencia y Tecnología de México (CONACyT) la financiación para realizar este trabajo enmarcado dentro de su Tesis Doctoral. [1] A. Fujishima, K. Honda, Nature 1972, 238, 37. [2] Z. Li, W. Luo, M. Zhang, J. Feng, Z. Zou, Energy Env. Sci 2013, 6, 347. [3] J. Li, N. Wu, Catal Sci Technol 2015, 5, 1360. [4] M. Barawi, E. Flores, I. J. Ferrer, J. R. Ares, C. Sánchez, J Mater Chem A 2015, 3, 7959. [5] E. Flores, J. R. Ares, I. J. Ferrer, C. Sánchez, Phys. Status Solidi RRL - Rapid Res. Lett. 2016, 10, 802. [6] M. Barawi, J. M. Clamagirand, M. Ponthieu, S. Yoda, J. R. Ares, J. Bodega, J. F. Fernández, I. J. Ferrer, F. Leardini, C. Sánchez, Revista de la RSEF 2013, 27, 47.
        Speaker: Mr. Eduardo Flores (Dpto. de Física de Materiales M-04, Facultad de Ciencias, Universidad Autónoma de Madrid)
    • 15:15 19:00
      Magnetic Materials and Applications (CEMAG) Aula Química Analítica (Facultad Química (USC))

      Aula Química Analítica

      Facultad Química (USC)

      • 15:15
        Functionalized Hybrid Nanomagnets: New Materials for Innovations in Energy Storage and Medical Theranostics 45m
        Imagine a future in which food is used to activate specific immune reactions in a human body based on an external noninvasive magnetic stimulus. Dream of a material that stores and releases energy reversibly by temperature changes between day and night. These visions may be realized by using magnetic nanoparticles that are functionalized to be biocompatible, environmentally stable and recyclable, self-healing, and low-cost. In this presentation I will discuss the basic concepts of magnetic nanomaterials and their magnetic properties with a focus on how to tune specific parameters in a controlled fashion to achieve the dreams of the future. I will highlight state-of-the-art experimental technologies that allow us to understand microscopic properties and interactions in relation to electronic structure changes caused by changes in size, shape, and composition of nanomaterials. Then I will discuss how this understanding is used when nanomagnets are functionalized for targeted drug delivery or composed to form macroscopic materials for new energetic applications like magnetic refrigeration. I will demonstrate that the seemingly complex behavior of hybrid metal/metal, metal/oxide, or oxide/oxide interface materials can be understood from the three fundamental interactions in magnetism: magnetic exchange interaction due to orbital overlap, spin-orbit interaction due to inner- and intra-atomic relativistic corrections (e.g., crystal field effects) and the long-range magnetic dipolar interaction. Several examples will be presented, including the formation of above-room-temperature ferromagnetic interface layers between low-temperature antiferromagnetic layers and the evolution of lattices of magnetic textures (skyrmions) in confined dimensions. The talk will end with an episode in the life of an imaginary golf-playing couple in the year 2040 who use their “Smart Magnet” (SMAG) phone to energize and heal their bodies on the green.
        Speaker: Prof. Michael Farle (University of Duisburg-Essen, Germany, and Immanuel Kant Baltic Federal University, Russia)
      • 16:00
        ADVANCES IN MAGNETIC FORCE MICROSCOPY IMAGING: FROM PERMANENT MAGNETS TO BACTERIA 15m
        Despite decades of advances in magnetic imaging, obtaining direct, quantitative information with high spatial resolution remains an outstanding challenge. The imaging technique most widely used for local characterization of magnetic nanostructures is the Magnetic Force Microscope (MFM), which is indeed a very active topic of investigation. Advantages of MFM include relatively high spatial resolution, simplicity in operation as well as sample preparation, and the capability to applied in situ magnetic fields to study magnetization process [1, 2]. Recently we have also demonstrate the possibility of operate in different environments including liquid media that allow us to investigate biological samples [3]. In the present work we try to approach some of the challenges of MFM, spatial resolution, sensitivity and quantitative measurements, by following different routes. One route is the development of high-performance MFM probes with sub-10 nm (sub-25 nm) topographic (magnetic) lateral resolution by following different easy and quick low-cost approaches. This allows one to not only customize the tip stray field, avoiding tip-induced changes in the sample magnetization, but also to optimize MFM imaging in vacuum (or liquid media) by choosing tips mounted on hard (or soft) cantilevers, a technology that is currently not available on the market [4]. In Figure 1 we show an example of the advantages of tune the mechanical properties of the cantilever. We compare the MFM images of a reference sample (a commercial high disk) acquired with a commercial MFM tip (Figure 1 a and b) and a custom-made probe (Figure 1 c and d) at ambient conditions and in liquid environment. It is well known that due to the viscosity of the liquid media there is a decrease in the quality factor of the cantilever and, for that reason, an increase of the noise in the MFM images. Using specific customized MFM probes we can enhance the signal in about a factor of 10 and improve significatively the quality of the images. Moreover, with this customized MFM probes we can obtain MFM images of biological materials in physiological conditions. In figure 2 we present the topography and the magnetic signal of magnetotactic bacteria Magnetospirillum gryphiswaldense [5] acquired with custom made MFM tips. Furthermore, the idea of explore new MFM probe architectures [6] allow us to focus some of the challenges of the technique as the lack of quantitative information. In that sense, alternative advanced methods as measuring energy dissipation with MFM is of great interest not only for nanomechanics but also to understand important energy transformation and loss mechanisms that determine the efficiency of energy of data storage device [7]. Acknowledgments We acknowledge the support from the Spanish Ministerio de Economia y Competitividad (MINECO) under projects no. MAT2013-48054-C2-1-R, Consolider CSD2010-00024, MAT2015-73775-JIN and MAT2016-76824-C3-1-R. References [1] M. Jaafar, L. Serrano-Ramón, O. Iglesias-Freire, A. Fernández-Pacheco, M.R. Ibarra, J.M. De Teresa, A. Asenjo, Nan. Res.Lett 6, 1 (2011) [2] E. Berganza, C. Bran, M. Jaafar, M. Vázquez, A. Asenjo, Sci. Rep. 6, 29702 (2016) [3]P. Ares, M. Jaafar, A. Gil, J. Gómez –Herrero, A. Asenjo, Small, 11, 4731–4736 (2015) [4] O. Iglesias – Freire, M. Jaafar, E. Berganz, A. Asenjo, Beilstein J. Nanotechnol. 7, 1068-1074 (2016) [5] A. M. Huízar-Félix, D. Muñoz, I. Orue, C. Magen, A. Ibarra, M. Barandiarán, A. Muela, M.L. Fernandez- Gubieda, Appl. Phys. Lett., 108, 6, 10.1063, (2016) [6] H. Campanella, M. Jaafar,J. Llobet, J. Esteve, M. Vázquez, A. Asenjo, R. P. del Real and J. A. Plaza, Nanotechnology, 22, 505301(2011) [7] M. Jaafar, O. Iglesias- Freire, P. García- Mochales, J.J. Saénz, A. Asenjo, Nanoscale 8, 16989-16994 (2016)
        Speaker: Dr. Miriam Jaafar (Instituto de Ciencia de Materiales de Madrid)
        Slides
      • 16:15
        Improved Performance of Assemblies of Magnetic Nanocrystals for Heat Delivery and Magnetic Guidance Applications 25m
        Nanoparticles of magnetic materials are very useful in different bio-related applications, on which the combination of chemistry and magnetic performance will determine their final purpose. Two examples of magnetic nanoparticles synthesized and manipulated by wet-chemistry methods will be detailed to demonstrate how to exert control over the final magnetic behavior and over their ultimate functionalities, considering heat delivery or magnetic guidance of self-propelled swimmers.
        Speaker: Dr. Verónica Salgueiriño (Departamento de Física Aplicada, Universidade de Vigo)
      • 16:55
        Coffee Break 20m
      • 17:15
        Spin Hall effect in heavy metals: mechanisms and optimization 25m
        The discovery of new spin-to-charge conversion effects (spin Hall effect (SHE), Rashba-Edelstein effect, spin-momentum locking) is expanding the potential of applications such as the magnetization switching of ferromagnetic elements for memories [1] or the recent proposal of a spin-orbit logic [2] which can have a strong technological impact. Finding routes to maximize the SHE is not possible as long as it remains unclear which is the dominant mechanism in a material. I will present a systematic study in Pt, the prototypical SHE material, using the spin absorption method in lateral spin valve devices. We find a single intrinsic spin Hall conductivity in a wide range of conductivities, in good agreement with theory. By tuning the conductivity, we observe for the first time the crossover between the moderately dirty and the superclean scaling regimes of the SHE, equivalent to that obtained for the anomalous Hall effect. Our results explain the dispersion of values in the literature and find a route to maximize this important effect [3]. We also studied the mechanisms in Ta, a material with a claimed giant SHE. Finally, I will show how to optimize the spin-to-charge current conversion at room temperature by combining Pt with a graphene channel [4], opening up exciting opportunities towards the implementation of spin-orbit-based logic circuits. [1] C. K. Safeer et al., Nat. Nanotech. 11, 143 (2016) [2] S. Manipatruni et al., arXiv:1512.05428 [3] E. Sagasta et al., Phys. Rev. B 94, 060412(R) (2016) [4] W. Yan et al., arXiv:1702.01971 (accepted in Nature Comms.)
        Speaker: Prof. Felix Casanova (CIC nanoGUNE)
        Slides
      • 17:40
        On the importance and estimation of local heat dissipation of interacting magnetic nanoparticles subjected to an applied magnetic field 15m
        Controlling the heat dissipated by magnetic nanoparticles (MNPs) subjected to an alternating magnetic field HAC is crucial for the effectiveness of several applications such as heat-mediated drug delivery, which uses the heat generated by MNPs attached to some thermo-sensitive carrier to activate the release of the drug; or magnetic fluid hyperthermia (MFH), a promising technique for cancer treatment which uses the heat released by MNPs under AC fields to damage the cancer cells. Some experiments1,2,3 reported that during the exposure of MNPs to an AC field, the temperature may increase several tens of kelvins at the particle surface and then rapidly decay to zero only a few nanometers away. Therefore, addressing the local (at individual particle level) heat dissipation becomes very relevant4. In MFH, global (whole system) heat dissipation is usually obtained from the area of the magnetization vs. applied field M(H) hysteresis loops. However, using the same approach for local hysteresis cycles is not adequate for strong-interacting systems because coupled particles may have inverted hysteresis loops and therefore negative hysteresis areas. The aim of this work is to find an alternative way to evaluate local released energy. To do so, we work with the kinetic Monte Carlo technique, which is suitable to describe heating processes of interacting particle systems5. Our premise is that the hysteresis area of the entire system stands for the total dissipated energy. We developed an approach where we analyze the different types of jumps of the energies of individual particles and from there we are able recover the area of the entire system. This work was cofinanced by the Spanish MINECO (Project MAT2013-47078-C2-2-P), Xunta de Galicia, Spain (Project GRC 2014/013, ‘Programa de axudas á etapa predoutoral’ and financial support of D.S. under Plan I2C) and ‘Fondo Social Europeo 2014/2020’.
        Speaker: Ms. Cristina Munoz-Menendez (Instituto de Investigacións Tecnolóxicas and Departamento de Física Aplicada, Universidade de Santiago de Compostela, Spain)
        Slides
      • 17:55
        Motion of magnetic textured controlled by temperature gradients and acoustic waves 25m
        Introduction The ability to control the motion of magnetic structures, like domain walls (DW), is a key point in the development of many spintronic and magnetic devices. The traditional ways to control their motion areis by means ofusing magnetic fields and spin polarized currents. MAlso, magnetic domain motion driven by temperature gradients hasave been also shown in theoretical [1,2] and experimental [3] works, opening the door to use thermal control of domain wall in future spintronicmagnonics devices. On the other hand, the possibility to control the magnetic properties using mechanical stress is currently being investigated with promising results [4,5]. In this work we will focus in these two ways to control the dynamics of magnetic textures, studying: 1) the dynamics of complex magnetic textures, like spin spirals or skyrmions, induced by thermal gradients. 2) the possibility to use acoustic waves as the driven force for the DW motion. Motionvement induced by temperature gradients The existence of a temperature gradient in the system induces a non-equilibrium populationsituation of magnons. The density of magnons excited in the hotter isare larger than that in the cold section of the system, leading to a flow of magnons from the hotter area to the colder one. When the magnons pass through the DW, they transfer angular momentum to the DW and as a consequence of that effect the DW moves to the colder area. Recently, F. Schlickeiser et. al have proposed that in parallel to the transfer angular momentum other mechanism may exist responsible of the movement of magnetic structures into a temperature gradient. Such mechanism is related to the maximization of the entropy of the system by displacing the DW from the colder to the hotter area [6]. In our work, we analyze the dynamics of two dimensional non-collinear magnetic textures subject to a temperature gradient. In order to do that, numerical calculations of the dynamics of a helical spin spiral (HSS), a skyrmion lattice and isolated skyrmions are carried out in atomistic spin models with the stochastic Landau-Lifshitz-Gilbert equation of motion. Fig1: Helical spin spiral (HSS) velocity versus temperature gradient for, α=0.2. The open symbols present our numerical data, the lines are from linear fits to the positive and negative temperature gradient dT/dx. Our findings show that in systems with spin spirals the lack of mirror symmetry leads to the effect that the velocity of the moving spiral depends on the sign of the temperature gradient with respect to the chirality of the HSS. This result is clearly shown in the Fig. 1, where the velocity of a left-handed helical spin spiral (HSS) versus the temperature gradient is displayed for a value of the damping constant, α=0.2. .The data points (empty symbols) are from the numerical simulations while the lines represent linear fits to the positive and negative temperature gradient , dT/dx . Furthermore, we observe that the movement of isolated skyrmions is determined by the temperature gradient and the Magnus force, and in the case of a lattice of skyrmions the interaction between skyrmions plays a fundamental role. Motionvement induced by acoustic waves In our study of the mechanical control of the DW motion we use micromagnetic simulations to investigate whether it is possible to move a DW using mechanical waves, a possibility that has been suggested recently [43]. To do that we have developed a novel numerical scheme to solve both: magnetization dynamics and elastodynamics equations self-consistently, similar to the one presented in [54] but using a finite difference scheme. We consider a Ni nanowire of a rectangular cross section (50 x 20 nm) with a head to head DW in the middle. Circularly polarized elastic waves are excited ion one end of the nanowire by imposing a periodic deformation of amplitude uo and frequency ʋ=10Ghz. The mechanical excitation induces magneto-elastic waves (MEW). When they reach the DW they excite it, exerting a torque on such magnetic texture which induces a movement of the DW towards the source of the elastic excitation. This result is clearly shown in the Fig. 2, where the x-component of the averaged magnetization (which is related to the position of the DW) is plotted as a function of time for several values of the amplitude of the mechanical excitation. Fig1: Time evolution of the averaged x-component of the magnetization of the nanowire as a function of the amplitude uo of the acoustic excitation. Acknowledgments This work was partially supported by No. SA090U16 from the Junta de Castilla y Leon. References [1] D. Hinzke and U. Nowak, Phys. Rev. Lett, 107 (2011) 027205. [2] P. Yan et al, Phys. Rev. Lett, 107 (2011) 177207. [3] W. J. Jiang et al. Phys. Rev. Lett, 110 2013) 177207. [4] V. Sampath et al, Nano Lett. 16 (2016) 5681. [5] Na Lei et al, Nat. Comm. 4 (2012) 2386. [6] F. Schlickeiser et al Phys. Rev. Lett, 113 (2014) 097201.
        Speaker: Dr. Rocio Yanes (Universidad de Salamanca)
      • 18:20
        Chiral Organic Molecules for Molecular Spintronics Applications 15m
        Chiral molecules are fascinating objects lying behind some deep, still unexplained puzzles of Nature such as the fundamental asymmetry found in living beings, which only utilize molecules with a specific helicity, called enantiomers. The relationship between chirality and magnetism has long puzzled researchers. Recently, layers of purely organic chiral molecules have been shown to scatter electrons differently depending on their spin [1] or to induce the appearance of strong spin polarization in initially unpolarized electron currents [2], opening up the possibility to use these materials as spin filters or to control enantioselective reactions by means of spin polarization. In this work we report on an experimental study of different spin-related phenomena observed in layers of chiral molecules adsorbed on single-crystal metal surfaces. Monolayer-thick films of chiral 1,2-diphenyl-1,2-ethanediol (DPED) have been studied by means of spin-polarized, angle-resolved photoemission (SPARUPS) at the MAX-lab synchrotron in Lund, Sweden [3]. This molecule has two chiral centers located at the two carbon atoms of the ethane chain and presents two chiral enantiomers which are designated according to their conformation and optical activity as (R,R)-(+)-DPED and (S,S)-(–)-DPED. The molecular layers were adsorbed in ultra-high vacuum on top of ferromagnetic Co films epitaxially grown on Cu(100) whose in-plane spin polarization served as an in situ reference. The photoelectons emitted through adsorbed layers of both chiral enantiomers display a clear spin polarization at room temperature, independent of their binding energy. Nevertheless, as Figure 1 shows, the spins point along different directions in space: in-plane for (R,R)-(+)-DPED and out-of-plane for (S,S)-(–)-DPED, which makes the DPED molecule a prototype system to study enantioselective spin filtering. These results will be compared to other recent experiments carried out on a similar molecule, 1,2-diphenylethylenediamine, adsorbed on Cu(100), highlighting the importance of the substrate and the charge transfer between this matter and the adsorbate. One of the main characteristics of chiral molecules is their optical activity, that has long been known and studied for the visible and UV wavelengths but not so much in the x ray range. Enantio-pure ultrathin films of DPED adsorbed on Cu(100) at 100 K have also been studied at MAXlab using circularly polarized x rays absorption (XAS) at the carbon K edge. XAS excites element-specific core electrons to empty levels in the ground state thus probing the molecule's electronic configuration. Pairs of spectra with circularly polarized x rays of opposite helicity were acquired and compared by taking their intensity ratio. Several clearly dichroic features have been observed (see Figure 2) and assigned to transitions into empty C–C and C–H π-type molecular orbitals; as expected, these dichroic ratios show opposite signs for the two enantiomers studied. However, the magnitude of the asymmetry measured is much larger than expected for the natural circular dichroism associated to the chiral configuration of the molecule. Preliminary analysis of these data indicates that the charge transfer between the Cu(100) substrate and the DPED molecules upon adsorption might be enantio-selective and strongly polarized in orbital moment. The results described above suggest that this type of compounds may be useful for molecular spintronics applications.
        Speaker: Dr. Juan José de Miguel (Universidad Autónoma de Madrid)
      • 18:35
        Magnets solve problems 25m
        Magnets Solve Problems by Xavier Marti I spent my Phd trying to improve magnetic memories but I never had a chance to actually touch one – even less to “control it with electric fields”. Nevertheless, I collected enough academic merits as to receive a post-doc invitation to University of California, Berkeley, where things did not massively improve. At this stage, I realized that if I wanted to build complete objects using “spintronics”, I'd need to take a parallel road. Then, I became co-owner of IGSresearch. Leading the design of devices based on simple -simple!- applications of spintronics has really changed my life and, yet, improved by academic CV as well. Our company has lead the production of simple anisotropic magnetoresistive devices used to accurately manage outdoor parkings in smart cities.(This product has now become E.ON's primary product for smart parking being distributed among 11 countries in EU; likewise, Telefonica is deploying Spinwire in South America; we are now literally sweating to get those operating in Middle East). Many of academic colleagues greet me by saying “so you finally left Science!” or, sometimes the most urgent question referring Spinwire is “Did you actually fabricate each one of the nanometric bars inside it?”. Those sentences truly surprise me. Honestly, I have never before used as much the “scientific method” as I do nowadays. How would you call then devices involved in unprecedented geological monitoring or everyday evolving anti-terrorism security that we are equally working on? I spent a great amount of my time thinking about the so-called “technology transfer” and what could do our nation to turn all this “excellence” into a “sustainable economy”. I will talk about that too. Xavi
        Speaker: Dr. Xavi Marti (Chief Technological Officer IGSresearch | Permanent researcher at Institute of Physics of the Czech Academy of Sciences)
    • 15:15 19:00
      Molecular Electronics Aula Matemáticas (Facultad Química (USC))

      Aula Matemáticas

      Facultad Química (USC)

      • 15:15
        Spin transport, spinterface and spin photovoltaics in molecular films 30m
        Spin injection and transport into molecular semiconductors has attracted great interest recently, especially due to the small sources of spin decoherence in these materials [1]. However, there are still many open questions in this nascent field which range from the actual spin polarization at metal/molecular interfaces to the integration of molecular functionalities into spintronic devices. In this talk I will review several experimental highlights from our group. By using bathocuproine (BCP) and fluorinated copper phthalocyanine (FCuPc) we have unambiguously proved that spin transport occurs via molecular levels, finally dismissing any eventual role of metallic filaments or defects in the electronic transport [2,3]. Our experiments point to the critical role of the interfacial barriers for carrier injection into the molecular levels. Moreover, in the FCuPc case we have shown concomitant spin transport and photoresponse. Thanks to the emergence of two molecular-based properties, four distinguishable resistance states adjustable by light and/or magnetic field can be configured in a simple 2-bit memory cell [3]. Further recent results in this wide topic, merging spin transport with the photovoltaic effect of C60 fullerenes will be shown [4]. I also will present spin valves based on rare-earth quinolines. Here we highlight the role of metal/molecular hybridization in the spin polarization and its possible control [5-7].
        Speaker: Prof. Luis Hueso (CIC nanoGUNE)
      • 15:45
        Bioengineering a Single-Protein Wire 25m
        Biological Electron Transfer (ET) is the key step in many basic cellular processes such as respiration and photosynthesis [1]. Nature has developed highly specialized molecular building blocks capable of transporting charge with unprecedented efficiency, i.e. fast and at long distances [2]. Understanding the mechanisms behind biological ET is key to elucidate the changes in the charge transport regime caused by specific structural variations of the associated molecular machinery, which ultimately lead to, for instance, malfunctioning of the mitochondria. Fundamental knowledge gained from studying biological ET can also be exploited to design bioelectronic devices. Such studies would ultimately unveil what are the key parameters to be controlled in the transduction of electrical signals from active biomolecules, and direct us to the design of the next generation of highly specific optoelectronic sensors [3]. In order to comply with the downsizing demands of the microelectronics industry, the latest bioelectronic advances focus on bottom-up perspectives [3], aiming for maximum sensitivities, high signal-to-noise ratios and enhanced efficiency in order to reduce energy consumption. Model redox proteins have been integrated in nano/micro-scale devices as the charge transport material. Cu-Azurin conductance signatures have been recently observed in microscale solid-state devices [4-6], which demonstrates their compatibility when hybridized to an electronic platform. Furthermore, Cu-Azurin and cytochrome b562 have also been extensively analysed at the single-protein level [7,8]. These pioneering studies established the sequential two-step ET tunneling mechanism for such systems26, and demonstrated the feasibility of such hybrid bio-interfaces to work as active components in nanoscale circuits. Here [9] we present an example of bioengineering charge transport in a single-protein wire. The copper-binding protein Azurin has been exploited to compare charge transport of single-protein devices made of a wild-type (Wt) structure and a mutant (K41C), where, in the latter, the natural lysine (Lys) 41 residue has been replaced by a cysteine (Cys) (Fig. 1a). This single point mutation has a two-fold effect; first, the new solvent-exposed thiol (-SH) group will serve as a new chemical connection to one of the external device terminals, and second, the modification is in the secondary coordination sphere of the Cu centre, which is expected to influence the metal redox behavior [10,11] and, hence, the transport regime through the protein matrix. Individual proteins of both variants were trapped between two metal electrodes in a physiological environment using an Electrochemical Scanning Tunneling Microscope (EC-STM) configuration, and the charge transport characterized as a function of an applied electrochemical gate voltage and temperature [12,13]. All-atom molecular-dynamics (MD) simulations suggest that the electrode-protein-electrode junction occurs via two well-localized sites on the protein, i.e. the hydrophobic patch and the natural Cys residues. Despite comparable orientations of both Wt and K41C proteins bridges are expected, the results show acute differences in the charge transport mechanism of the single-protein wire between the Wt and the mutant variant, observing in the latter a complete shutdown of the two-step sequential tunneling character typically described in the Wt [26]. Ab initio calculations of the relevant ET pathway fragment including the modified residue 41 show the poor participation of the Cu centre in the transport-relevant molecular frontier orbital of the K41C mutant. These results fully account for the observed conduction changes within the framework of coherent tunneling mechanism for the single-protein wire of bioengineered proteins. [1] E. Broda, The Evolution of the Bioenergetic Processes. (Elsevier, 2014). [2] H. B. Gray & J. R. Winkler, Proc. Natl. Acad. Sci. U. S. A. 102 (2005) 3534-9. [3] A. Zhang & C. M. Lieber, Chem. Rev. 116 (2015) 215-257. [4] L. Sepunaru, I. Pecht, M. Sheves, & D. Cahen, J. Am. Chem. Soc. 133 (2011) 2421-3. [5] W. Li et al., ACS Nano 6 (2012) 10816-24. [6] X. Yu et al., ACS Nano 9 (2015) 9955-9963. [7] Q. Chi, O. Farver & J. Ulstrup, Proc. Natl. Acad. Sci. U. S. A. 102 (2005) 16203-16208. [8] E. Pia et al., Nano Lett. 11 (2011) 176-82. [9] M. P. Ruiz et al., submitted to Nature Materials (2017). [10] N. M. Marshall et al., Nature 462 (2009) 113-6. [11] K. M. Lancaster et al., J. Am. Chem. Soc. 132 (2010) 14590-5. [12] I. Díez-Pérez et al., Nat. Chem. 1 (2009) 635-41. [13] A. C. Aragonès et al., Nature 531 (2016) 88-91.
        Speaker: Prof. Ruben Perez (Univesidad Autonoma de Madrid)
      • 16:10
        Electron transport through individual all-organic polyradicals 30m
        Organic radicals are neutral, purely organic molecules exhibiting an intrinsic magnetic moment due to the presence of an unpaired electron in the molecule in its ground state. This property, added to the low spin-orbit coupling makes organic radicals promising candidates for Molecular Spintronics provided that the radical character is stable in solid state electronic devices. We measure electron transport through individual PTM organic radicals. We show that the radical centre and therefore the magnetism, is preserved in a variety of individual neutral radicals in single-molecule solid state devices, ranging from monoradicals [1] to polyradicals [2,3] (di- and tri-radicals). The magnetism, in the shape of a Kondo anomaly, is robust against mechanical and electrical perturbations. In polyradicals (see Figure 1), where several unpaired spins are coupled via exchange coupling in a single high-spin purely organic molecule, we show that the local environment can induce a sign reversal of the exchange interaction, from ferro to antiferro, inducing a change in the magnetic ground state of the individual molecule [2]. In addition, diradicals can be reversibly and controllably charged preserving the radical character. The controlled access to different redox states of the molecule, allows to perform Inelastic Electron Tunnel Spectroscopy (IETS) of the spin spectra in both redox states and forms the basis of a SWAP quantum gate[3]. [1] R. Frisenda et al. Nano Lett. 15 (2015) 3109 [2] R. Gaudenzi et al. Nano Lett. 16 (2016) 2066 [3] R. Gaudenzi et al. ACS Nano (2017) DOI: 10.1021/acsnano.7b01578
        Speaker: Dr. Enrique Burzuri (Imdea Nanociencia)
      • 16:40
        Theoretical evaluation of [V(α-C3S5)3]2- as a nuclear-spin sensitive single-molecule spin transistor. 25m
        In a straightforward application of molecular nanospintronics to quantum computing, single-molecule spin transistors can be used to measure and control nuclear spin qubits, since a conductance jump occurs when the electronic spin inverts its polarization, and this happens at a specific magnetic field determined by the nuclear spin state. So far, this procedure has only been studied using TbPc2, the first known Single Ion Magnet. Here we theoretically explore the adequacy for this procedure of the highly stable molecular spin qubit [V(α-C3S5)3]2-. We determine the spin-dependent conductance and verify that, at the Fermi energy, the intrinsic electronic spin does not share spatial density distribution with the polarized current electrons, indicating that the spin states may survive in the conduction regime. We estimate some physical parameters to guide the experiments, and verify the robustness of the theoretical methodology by applying it to two chemically related vanadium complexes.
        Speaker: Dr. Salvador Cardona-Serra (Instituto de Ciencia Molecular)
      • 17:05
        Coffee Break 55m
      • 18:00
        Last advances on thin film organic lasers. 30m
        In the last years extensive research has been devoted to the investigation of optically-pumped solution processable thin film organic lasers, due to their advantages of chemical versatility, wavelength tunability, mechanical flexibility and low cost. Particularly attractive for applications in the fields of optical communications, biosensing and chemical sensing are distributed feedback (DFB) lasers, consisting of nanostructured active organic waveguides. In this context, our research group has performed extensive work on DFBs with different types of organic active materials and laser resonators. In this presentation the last advances achieved by our research group in improving both, the active laser material and the laser resonator, and their application as optical sensors of various kinds, will be discussed. This includes first, results on high performing laser dyes of two families: perylenediimides, PDIs, and carbon-bridged oligo(p-phenylenevinylene)s, COPVs, dispersed in thermoplastic polymer films, emitting in a wide range of wavelengths within the visible spectrum. Secondly, progress on the development of different device geometries based on one dimensional second-order DFB resonators fabricated by holographic lithography and nanoimprint lithography. The capability of these lasers to be used as label-free refractive index sensors, sensors for the specific detection of biomolecules of clinical interest, etc., will also be described.
        Speaker: Prof. María Ángeles Díaz García (Universidad de Alicante)
      • 18:30
        Modulating light emission in a spin-OLED through spin injection at high voltages 30m
        Spin-based electronics is one of the emerging branches in today’s nanotechnology and the most active area within nanomagnetism. So far spintronics has been based on conventional materials like inorganic metals and semiconductors. Still, an appealing possibility is that of using molecule-based materials, as components of new spintronic systems. In particular, by taking advantage of a hybrid approach one can integrate molecular materials showing multifunctional properties into spintronic devices. In this talk we illustrate the use of this approach to fabricate multifunctional molecular devices combining light and spin-valve properties (i.e., Spin-OLEDs).
        Speaker: Dr. Helena Prima Garcia (Instituto de Ciencia Molecular (Valencia))
    • 15:15 18:45
      Particle and Theoretical Physics I Aula Química Técnica (Facultad de Química (USC))

      Aula Química Técnica

      Facultad de Química (USC)

      • 15:15
        Radiative b-baryons decays at LHCb 30m
        Este análisis consiste en el estudio de las desintegraciones de bariones pesados con un quark b (Lambda_b, Xi_b y Omega_b ) con un fotón en el estado final. Esto tiene un doble interés: - Las desintegraciones radiativas de bariones pesados no han sido observadas. Se pretende medir la fracción de desintegraciones de los canales antes mencionados. - El Modelo Estándar (ME) predice que en las desintegraciones raras del tipo b->s gamma el fotón tiene polarización levógira, y cualquier desviación al respecto implicaría la existencia de Nueva Física. Motivado por esto, se usará la distribución angular de los canales mencionados para extraer la polarización del fotón en este tipo de desintegraciones. Para este último punto se discutirán las sensibilidad esperadas debido a los efectos del detector LHCb.
        Speaker: Luis Miguel García (IFIC)
        Slides
      • 15:45
        Weak-lensing magnification as a probe for the dark Universe 30m
        Introduction Cosmological measurements show that the expansion of the Universe is accelerating. Generically, the entity that causes this acceleration (whether it is a new form of matter or modified gravity) is called dark energy [1]. Nevertheless, the nature of dark energy constitutes one of the biggest puzzles in Physics. Shedding light on dark energy requires the construction of big experiments that survey large volumes of the Universe. One of those experiments is The Dark Energy Survey (DES) [2]. One of the observational probes that may unravel the nature of dark energy is the weak gravitational lensing [3]. Weak-lensing is produced by the gravitational bending of the trajectory of photons by gravitational fields leading to the deflection of the light rays. Thus, the light emitted by foreground distant galaxies is deflected by the matter located between them and the observer. For extended sources, in addition to the change in position, this leads to two observational effects: an isotropic size enlargement (magnification) and an elongation/shrink along one axis (shear). Since the surface brightness is preserved, the isotropic size enlargement due to magnification produces an increase on the observed flux of the background galaxies. This allows to see galaxies that would be beyond the detection threshold if gravitational lensing was not present. Thus, nearby the lenses the observed density of sources is increased. This effect is known as number-count magnification and allows to probe the convergence profile of the lens sample selected, that is a proxy for the matter profile [4]. Weak-lensing magnification by voids Extensive wide-field programs have allowed accurate measurement of weak lensing effects. Previous magnification measurements involve the use of very massive objects as lenses, such as luminous red galaxies (LRGs) and clusters [5], or high redshift objects as sources, such as Lymanbreak galaxies (LBGs) or quasars (QSOs) [6,7]. Lyman break galaxies and quasars have demonstrated to be a very effective population of background samples to do magnification studies due to its high lensing efficiency. However, deep surveys or large areas are needed to reach a significant amount of these objects. Thus, shallow or small area surveys require the selection of a more numerous population of source galaxies to allow the measurement of the magnification signal. A new technique has been developed at the Dark Energy Survey [8], where galaxies selected only by its photo-z, are used both as lenses and sources. This procedure simplifies the analysis as no additional processing is needed to construct the sample (contrary to the methodology present on the literature). This new methodology allows the detection of the magnification signal on small area surveys, such as the DES Science Verification data-set, but the power of this methodology also applies to large area surveys such as LSST or the final footprint of DES, with 5000 deg^2 . The huge decrease on the shot-noise due to the increase on the surface density of sources, allows the selection of more exotic lenses, such as voids. Voids are the emptiest regions of the cosmic web that conform the large-scale-structure of the Universe (LSS) [9]. Thus, their structure and evolution is dominated by dark energy. Previous works on simulations show that different void properties such as their ellipticity or its total matter radial distribution (void-profile) is strongly dependent on the modified gravity model used [10-17]. Due to the presence of dark matter, the total matter distribution is only accessible through gravitational lensing. Thus, the determination of the void-profile with weak-lensing magnification constitutes a new and independent probe for dark energy. References [1] S. Perlmutter et al., ApJ 517 (1999) 565. [2] The Dark Energy Survey Collaboration, ArXiv astro-ph/0510346 (2005). [3] D. H. Weinberg et al., Phys. Rep. 530.2 (2013) 87. [4] M. Bartelmann and P. Schneider, Phys. Rep. 340 (2001) 291. [5] A. H. Bauer et al., MNRAS 440 (2014) 3701. [6] Ryan Scranton et al., ApJ 633.2 (2005) 589. [7] C. B. Morrison et al., MNRAS 426 (2012). [8] M. Garcia-Fernandez et al., ArXiv 1611.10326 (2016). [9] A. Kovács and J. García-Bellido., MNRAS 462 (2016), [10] F. von Braun-Bates et al., JCAP 3 (2017) 012. [11] G. Lavaux and B. D. Wandelt., MNRAS 403 ( 2010) 1392. [12] G. Lavaux and B. D. Wandelt., ApJ 754.2 (2012) 109. [13] D. Spolyar, M. Sahlén, and J. Silk., Phys. Rev. Lett. 111.24 (2013) 241103. [14] E. V. Arbuzova, A. D. Dolgov, and L. Reverberi., Astroparticle Physics 54 (2014) 44. [15] Y.-C. Cai, N. Padilla, and B. Li. ArXiv 1410.8355 (2014). [16] P. Zivick et al., MNRAS 451 (Aug. 2015) 4215. [17] A. Barreira et al., JCAP 8, (2015) 028.
        Speaker: Mr. Manuel Garcia-Fernandez (CIEMAT)
      • 16:15
        Medida del ángulo de mezcla theta13 en el experimento Double Chooz 30m
        El objetivo principal del experimento Double Chooz es conseguir una medida precisa del ángulo de mezcla de neutrinos theta13. Este parámetro, el más pequeño de los tres ángulos de mezcla conocidos, se puede determinar a partir de la desaparición de los antineutrinos electrónicos emitidos por los dos reactores de la central nuclear de Chooz, en Francia. Dichos antineutrinos interaccionan con los protones presentes en el líquido centelleador de los detectores mediante la desintegración beta inversa, produciendo la coincidencia temporal y espacial de dos señales que permiten una sustracción eficiente de los fondos del experimento. En este documento se presentan los últimos resultados obtenidos a partir de un análisis novedoso, que proporcionan la medida más precisa de theta13 conseguida por Double Chooz hasta la fecha.
        Speaker: Ms. Diana Navas Nicolás (Ciemat)
      • 16:45
        Search for new physics via baryon EDM at LHC 30m
        Permanent electric dipole moments (EDMs) of fundamental particles provide powerful probes for physics beyond the Standard Model. We propose to search for the EDM of strange and charm baryons at LHC, extending the ongoing experimental program on the neutron, muon, atoms, molecules and light nuclei. The EDM of strange Λ baryons, selected from weak decays of charm baryons produced in pp collisions at LHC, can be determined by studying the spin precession in the magnetic field of the detector tracking system. A test of CPT symmetry can be performed by measuring the magnetic dipole moment of Λ and anti-Λ baryons. For short-lived Λ+c and Ξc+ baryons, to be produced in a fixed-target experiment using the 7 TeV LHC beam and channeled in a bent crystal, the spin precession is induced by the intense electromagnetic field between crystal atomic planes. The experimental layout based on the LHCb detector and the expected sensitivities in the coming years are discussed, along with perspectives for the future.
        Speaker: Joan Ruiz Vidal (IFIC, University of Valencia - CSIC)
        Slides
      • 17:15
        Challenging the Standard Model with top quarks interactions 30m
        The elementary particles, their properties and their interactions are described by the Standard Model (SM), which is the theoretical framework for the study of the strong interactions of quarks and gluons and the unified electroweak force by means of a modelling framework based on local gauge invariance. The SM is very successful in accounting for most of the observed phenomena at the microscopic frontier of physics, verified and tested in many experiments in the last decades, also including the discovery of the Higgs boson by the ATLAS and CMS experiments at the LHC facility at CERN laboratory in 2012. However, new theories beyond the SM are still needed to explain many pending questions in physics: the matter-antimatter asymmetry, the pattern of flavour mixings and fermion masses, the nature of dark matter or the accelerated expansion of the Universe. The SM accommodates the measured masses, but it does not explain the vastly different mass scales spanned by the known particles. The dynamics of flavour and the origin of CP violation are also related to the mass generation, but still not fully understood. The SM should be either extended or replaced by a more general modelling framework, but experimental evidences are needed to point in which direction the SM should be modified. The top quark is a very sensitive probe of the electroweak symmetry breaking, since it is the heaviest fundamental particle with the SM framework.Its large mass makes the top very different from all other quarks, with a Yukawa coupling to the Higgs boson close to unity. For these reasons the top quark and the Higgs boson play very special roles in the SM and in many extensions thereof. An accurate knowledge of their properties (mass, couplings, production cross section, decay branching ratios) can bring key information on fundamental interactions at the electroweak breaking scale and beyond. Some of the top quark couplings were investigated at the Tevatron, while others, such as the coupling of the top quark to the Z or the Higgs boson are becoming accessible only with the high-statistics top quark sample at the LHC. This contribution provides a comprehensive overview of the latest ATLAS results for tt+Z/W and tt+H processes.
        Speaker: Dr. Maria Moreno Llacer (CERN)
      • 17:45
        Does a deformation of special relativity imply energy dependent photon time delays? 30m
        We analyze the observability of an energy dependence, due to departures from special relativity, in delays of arrival times of particles produced by very distant sources. We find different conclusions depending on the model used for the source and the model used for the departures from special relativity both in the case of Lorentz invariance violations and in the case of a modification compatible with the relativity principle.
        Speaker: Mr. Javier Relancio (Universidad de Zaragoza)
        Slides
      • 18:15
        Sincronización fina del trigger de las cámaras de tubos de deriva para el detector CMS del LHC 30m
        En la presente contribución se describe el trabajo de sincronización fina del sistema de disparo de las cámaras de deriva del detector CMS del LHC. Este estudio se ha realizado después de la actualización del sistema de disparo de las cámaras de deriva que ha tenido lugar a principios de 2016. La obtención de las correcciones en los retrasos de la señal de reloj que debe aplicarse a la electrónica de cada cámara es fundamental para el optimo funcionamiento del detector, pues estas correcciones optimizan la eficiencia del sistema de disparo. En la presente contribución se describe el método y los resultados obtenidos.
        Speaker: Adrian Alvarez Fernandez (Ciemat)
    • 15:15 19:00
      Physics of the Atmosphere and the Ocean Química Inorgánica (Facultad Química (USC))

      Química Inorgánica

      Facultad Química (USC)

      • 15:15
        Variabilidad de las propiedades físicas y su influencia en el ecosistema de la plataforma continental de A Coruña. 15m
        Análisis de la variabilidad espacial y temporal de la temperatura y la salinidad a partir de las series históricas obtenidas con una periodicidad mensual en el transecto de A Coruña del proyecto RADIALES del Instituto Español de Oceanografía (IEO).
        Speaker: Ms. Lucía Lado (Instituto Español de Oceanografía (IEO))
        Slides
      • 15:30
        The Santander Atlantic Time Series Station (SATS): Una serie de tiempo combinación de una estación hidrográfica mensual y el Observatorio Oceánico Biscay AGL 15m
        Entre los cometidos del Instituto Español de Oceanografía destaca el mantenimiento de series temporales de observaciones oceánicas. El programa RADIALES en concreto implica el muestreo mensual de propiedades hidrográficas y biogeoquímicas de la columna de agua en estaciones oceanográficas de transectos perpendiculares a la costa frente a Vigo A Coruña, Gijón, Cudillero y Santander. El radial de Santander está en funcionamiento desde el año 1991 y debido a la proximidad del talud continental frente a Santander, las estaciones más alejadas de la costa en esta sección muestrean mensualmente hasta más de 1500 metros de profundidad. El mantenimiento de programas de monitorización tiene por objeto la detección de tendencias a largo plazo esencial para comprender los cambios que están afectando al océano en el escenario actual de cambio climático y fuerte presión humana sobre los ecosistemas marinos. Sin embargo, las medidas in-situ y simulaciones más recientes y avanzadas indican que los procesos físicos a altas frecuencias de variabilidad pueden tener un impacto importante sobre la captación de calor y CO2 atmosférico y en los ciclos biogeoquímicos. A la vista de esto, la mayoría de los programas de monitorización existentes han reforzado sus capacidades de observación haciendo uso de gliders, boyas océano-meteorológicas, perfiladores autónomos, etc. Con este mismo propósito, en Junio de 2007 el IEO fondeó en aguas oceánicas del Golfo de Vizcaya la boya océano-meteorológica Augusto González de Linares (Biscay AGL) añadiéndose una nueva estación en su posición (43° 50.67 N; 3°46.2 W, 2850 metros de profundidad a 40 km de la costa, Fig. 1) al muestro mensual de propiedades hidrográficas y biogeoquímicas de la columna de agua en el radial de Santander [1]. La boya está equipada con un amplio conjunto de sensores que proporcionan datos horarios de los principales parámetros meteorológicos (presión atmosférica, temperatura del aire y velocidad y dirección del vientos); hidrográficos (temperatura y salinidad superficial del mar); y biogeoquímicos (oxígeno disuelto y clorofila) así como un ADCP para la medida de corrientes en los primeros 100 metros de la columna de agua y un sensor de oleaje direccional. Tanto las Radiales como la Biscay AGL forman parte del Sistema de Observación Oceánica del IEO (IEOOS) [2] El objetivo fundamental de la serie SATS será la integración de las medidas de la Biscay AGL y la estación 7 del Radial de Santander (Programa RADIALES) y su validación y calibración para poner a disposición de la comunidad científica y técnica de una serie de datos de alta calidad y frecuencia, para estudio de las importantes transformaciones que se han ido desarrollando durante las últimas décadas, incluido el cambio climático que en el Golfo de Vizcaya que se manifiesta con un importante incremento de temperatura en todas las aguas intermedias hasta el agua mediterránea a 1000m de profundidad, así como la generación de productos que visibilicen la información
        Speaker: Dr. ALICIA LAVIN MONTERO (INSTITUTO ESPAÑOL DE OCEANOGRAFIA)
      • 15:45
        De antiguos libros a recrear el método: El método de Schönbein para medir ozono 15m
        Introducción La recuperación de datos meteorológicos de fuentes documentales antiguas es de gran importancia para la comunidad científica. Es un arduo trabajo con gran labor de pesquisas y a veces hasta suerte. Algunas veces aparecen en estas fuentes de datos métodos de medición que a primera vista parecen desfasados e inútiles y a los cuales no se les da una oportunidad. Es en este trabajo donde desde la recuperación de datos pasamos a la recreación del método. En este trabajo presentamos una metodología para recrear uno de los primeros sistemas de medición de ozono diseñados en el S. XIX y verificamos la validez de las mediciones realizadas con él. Recuperación de datos Primero presentamos las series meteorológicas de finales del siglo XIX y principios del siglo XX localizadas en el observatorio de A Guarda, pionero en Galicia en este tipo de medidas y localizadas en ese tiempo en el “Colexio Xesuita Apóstol Santiago”. Las series de datos obtenidas fueron obtenidas de las notas meteorológicas publicadas en el periódico católico “La Integridad”, publicado en esas fechas en Tui (Galicia). Fueron revisados más de 1000 periódicos de esta publicación y fueron digitalizados, manualmente, más del 60000 medidas individuales. Aparte de las medidas anteriormente mencionadas en el periódico también aparecían previsiones meteorológicas bajo el nombre de “El Tiempo”. Añadimos también la verificación e interpretación de estos datos, (incluyendo los ciclos intraanuales). Esta validación se realizó a través de tres distintas bases de datos, incluyéndose también el análisis hecho [1]. Recreación del método Tras localizar datos de mediciones de ozono troposférico en las notas meteorológicas investigamos sobre el método usado y llegamos a la conclusión de que habría que revisar el método, ya que toda referencia bibliográfica tiene más de 30 años, aparte de que sufrió una demonización a lo largo del siglo XX a pesar de ser el más extendido y usado[2]. Buscamos las fuentes bibliográficas originales y recreamos el método tal cual se hacía en el siglo XIX. Se realizó una campaña de medición en condiciones de atmósfera libre para determinar si este método medía o no variaciones de ozono. Se presentaran las conclusiones obtenidas durante toda la campaña, conteniendo también los problemas confrontados en las campañas de medición y trabajo de campo. References [1] Añel J.A., et al., Weather (2017) [2] Bokjov R.D., J. Clim. appl. Met 25 (1986) 345-352.
        Speaker: Mr. Ignacio A. Ramírez-González (EPhysLab, Universidade de Vigo)
      • 16:00
        Recuperación de datos meteorológicos en Extremadura: primeros resultados 15m
        A excepción de los estudios sobre el clima de la región de Zafra desde 1750 hasta 1840 utilizando descripciones semanales del tiempo atmosférico que ha realizado nuestro grupo de investigación [1-3], la reconstrucción del clima en Extremadura en los últimos siglos haciendo este tipo de ejercicios está, simplemente, por hacer. Además, a día de hoy, los archivos y bibliotecas de Extremadura no han sido consultados sistemáticamente para extraer de ellos informaciones relevantes sobre el clima del pasado. Nuestro equipo de investigación ha realizado algunas exploraciones previas que revelan que los archivos extremeños tienen un enorme potencial en este sentido, especialmente en la recuperación de datos. Los primeros datos meteorológicos localizados de Extremadura fueron tomados en Zafra (Badajoz) en la década de 1820. En la ciudad de Badajoz, disponemos de datos meteorológicos diarios desde 1830 a 1833, publicados en la prensa local [4]. En la provincia de Cáceres, los primeros datos que hemos localizado son de 1844, publicados en un periódico de la capital cacereña. También contamos con la estación meteorológica de Badajoz, en funcionamiento ininterrumpido desde 1860. De cara a los estudios de homogeneización de los datos de Badajoz, merece la pena destacar que contamos con una estación portuguesa cercana (la estación de Campo Mayor a tan sólo 15 km de distancia) desde 1861. Además, también se tomaron datos meteorológicos de una manera regular durante gran parte del siglo XIX en los balnearios de Baños de Montemayor (Cáceres) y de Alange (Badajoz). Y podemos incluso citar que la provincia de Badajoz contó con la primera red meteorológica española privada [5]. Todo esto nos indica que la región de Extremadura tiene un enorme potencial para actividades de recuperación de datos meteorológicos de los siglos XIX y XX. ¿Es posible extender en el tiempo las series meteorológicas de Badajoz y Cáceres? La agencia estatal AEMET proporciona valores diarios de las principales variables meteorológicas desde 1901 y 1907 para Badajoz y Cáceres respectivamente. No obstante, también proporciona valores mensuales anteriores para la serie de Badajoz. En la biblioteca de la delegación territorial de AEMET-Extremadura (en el campus universitario de Badajoz), se encuentran los libros originales manuscritos de las estaciones de Badajoz y Cáceres. Los dos primeros libros de observaciones de Badajoz contienen los datos diarios desde 1864 hasta 1900. Obviamente, aparecen numerosas variables meteorológicas. Por lo tanto, es factible obtener datos diarios a partir de esta fuente desde el año 1864, aunque con algunas importantes lagunas. Podemos indicar también que hay varios pliegos sin encuadernar de la estación meteorológica de Valdesevilla (aproximadamente de la década de 1880). ¿Es posible encontrar datos diarios para rellenar los huecos mencionados? Creemos que se pueden recuperar con cierta facilidad datos meteorológicos diarios extremeños del siglo XIX a partir de los números de la “Gaceta de Madrid”, principalmente de la década de 1880 (con datos de las estaciones de Badajoz, Cáceres y Valdesevilla). Los primeros datos meteorológicos extremeños que hemos encontrado en la “Gaceta de Madrid” son los de Badajoz, que comienzan a publicarse el 1 de noviembre de 1864. A partir del 25 de octubre de 1880, también hay datos de Cáceres (que acaban aproximadamente en 1889). También hay datos de la estación de Valdesevilla en esa década. En general, se publican datos del día anterior de presión, temperatura, dirección e intensidad del viento y estado de la atmósfera tomados a las 9 horas (se supone que en tiempo local). Hemos detectado unos (pocos) periódicos extremeños con datos meteorológicos del siglo XIX. Una búsqueda exhaustiva de éstos llevaría bastante tiempo. Estos periódicos son: “Boletín de la Agencia de Cáceres”, “Boletín-Revista del Instituto de Badajoz”, “Diario de Badajoz”, “Diario de Cáceres”, “El Avisador de Badajoz”, “El Iris” y “El Oliventino”. También merece destacarse la publicación “Revista de Extremadura”, donde hay comparaciones de datos simultáneos medidos en Badajoz y en Cáceres, así como datos mensuales de una estación colocada en el patio de una casa de Cáceres. Además, contamos con otras fuentes. En los resúmenes de observaciones del Observatorio de Madrid (o del organismo competente de la época) pueden encontrarse datos meteorológicos de Extremadura del siglo XIX (al menos, de Badajoz, Cáceres, Don Benito y Valdesevilla). Lamentablemente, estos resúmenes tan sólo contienen datos mensuales. Dentro de este ambicioso trabajo de recuperación de datos meteorológicos de Extremadura, hemos comenzado a dar los primeros pasos, que serán brevemente mencionados aquí: a) Recuperación de los datos meteorológicos del antiguo aeródromo de “Las Bardocas”. Hay documentación de archivo que atestigua su funcionamiento a partir de los años 1920. Se vislumbra en esta documentación que dicha infraestructura se trasladó a las actuales instalaciones de la Base Aérea de Badajoz-Talavera la Real, pues el terreno en el que se situó el aeródromo de “Las Bardocas” era una zona inundable. Asociado a dicho aeródromo, situado a 3 km del centro urbano de la ciudad de Badajoz, había un observatorio meteorológico (-6º 56’ 27’’ W y 38º 54’ 15’’ N). Se han realizado trabajos que han permitido el hallazgo de los cuadernos de observación originales y el rescate de los datos meteorológicos, registrados en el observatorio del Aeródromo de Badajoz “Las Bardocas”, durante los años 1948-1954. Se ha realizado también un análisis preliminar de los mismos. Las variables cuyos datos se han recuperado hasta la fecha son temperatura observada cada tres horas, temperaturas extremas diarias, humedad, precipitación, presión y viento, resultando de los primeros análisis que dichos datos son climatológicamente coherentes con los de los observatorios de Badajoz, y de la Base Aérea de Badajoz-Talavera la Real (las observaciones en esta nueva instalación aérea comienzan en 1955). Primero, se organizaron y clasificaron los documentos estructurados en libros por años y meses. Después, se escanearon para conservarlos en formato imagen (.JPG) en soporte digital. Y, más tarde, se digitalizaron los valores numéricos en ficheros Excel. b) Recuperación de datos diarios de insolación en Badajoz desde septiembre de 1928. Hemos iniciado la recuperación de esta serie de insolación de casi 90 años, de carácter excepcional en el marco de los datos de insolación en España [6]. Los resultados previos indican que la serie no tiene huecos importantes. c) Recuperación de datos de sondeos aerológicos. En 1924, comenzaron en el observatorio de Badajoz la observación de vientos en altura mediante el seguimiento de globos piloto. Se han localizado los cuadernos de observación originales de los años 1924 a 1953 y se ha documentado el método de observación. Se sabe que las observaciones continuaron hasta 1970, al menos. Sin embargo, lamentablemente, de los años posteriores sólo se han encontrado, hasta el momento, resúmenes hasta 1960. d) Recuperación de datos actinométricos de Cáceres. Se han encontrado datos diarios actinométricos de la Estación Meteorológica de Cáceres (con algunos huecos) medidos con un actinómetro de Arago en el período 1913-1923. Se está trabajando con esta serie de medidas actinométricas para hacer un estudio estadístico-climatológico de los datos. Este trabajo ha sido parcialmente financiado por la Junta de Extremadura (GR15137) y por el Ministerio de Economía y Competitividad del Gobierno Español (AYA2014-57556-P). Referencias [1] M.I. Fernández-Fernández et al., Clim. Change 126 (2014) 107. [2] M.I. Fernández-Fernández et al., Clim. Change 129 (2015) 267. [3] M.I. Fernández-Fernández et al., Clim. Change 141 (2017) 671. [4] F. Domínguez-Castro et al., Int. J. Clim. 34 (2014) 593. [5] J.M. Vaquero, M.C. Gallego, Rev. Esp. Fís. 14(4) (2000) 58. [6] A. Sanchez-Lorenzo et al., J. Geophys. Res. 112 (2007) D20115.
        Speaker: Dr. José Manuel Vaquero (Universidad de Extremadura)
      • 16:15
        A high-resolution picture of Euro-Atlantic climate variability during the Late Maunder Minimum 15m
        The Late Maunder Minimum (LMM, 1685-1715) denotes the climax of the Little Ice Age (LIA, cf. 1400-1700), which was one of the coldest periods in the last millennium. The LMM is a period of great interest since it was one of the few cold periods in recent centuries that persisted for several decades. Here, we present the first direct instrumental evidence of the daily atmospheric circulation over the eastern Atlantic during the LMM based on wind direction observations taken aboard ships over the English Channel. To do so, we derived two sets of monthly atmospheric circulation indices based on the persistence of the wind direction in the four cardinal directions and in 8-point wind roses for the 1685-2014 period. They provide the longest observational records of the atmospheric circulation to date, allowing us to explore the variability of the atmospheric circulation in a wide range of time-scales. The analysis of these indices indicate that the LMM was characterized by a pronounced meridional circulation and a marked reduction in the frequency of westerlies all year round, as compared to the present (1981-2010). The winter circulation contributed the most to enhance the cold conditions through an overall increase of northerly winds. Nevertheless, our findings also show a LMM more heterogeneous than previously thought, displaying contrasting spatial patterns in circulation and temperature, as well as large decadal variability. Based on the circulation characteristic of each winter, we provide a new observational-based catalogue of winters for the LMM, reassessing the indirect evidences available in the literature about the temperature conditions of the LMM. Our assessment confirms the majority of extremely cold winters documented in the literature, but also uncovers the existence of additional undocumented cold winters and a substantial number of mild winters that had been unnoticed so far. The outcomes also suggest a non-stationarity of the North Atlantic Oscillation (NAO) pattern within the LMM, which has not been reported before, with extremely cold (moderate) winters being associated to negative phases of a “high-zonal” (“low-zonal”) NAO pattern.
        Speakers: David Barriopedro (Instituto de Geociencias (IGEO, CSIC-UCM)), Javier Mellado (University of Lisbon, CGUL, IDL, Lisbon, Portugal)
      • 16:30
        La nueva versión del “número de manchas solares”: consecuencias para las ciencias atmosféricas 15m
        A mediados del siglo XIX, Rudolf Wolf [1-2] definió el “número relativo de manchas solares” de una manera un tanto arbitraria: multiplicaba por diez el número de grupos que eran observados sobre la fotosfera y sumaba el número total de manchas individuales que podía contar el observador. Pese a su simpleza, este índice resultó de gran utilidad en los estudios solares y en la física terrestre-solar. Así, el vulgarmente conocido como “número de manchas solares” (sunspot number) se convirtió con el tiempo es una de las series temporales más famosas de la estadística, la astrofísica y la geofísica [3]. Sin embargo, dos investigadores americanos realizaron en la década de 1990 un enorme esfuerzo para obtener una versión independiente del “número de manchas solares” que denominaron “Group Sunspot Number”. Recuperaron una gran cantidad de antiguas observaciones e idearon una metodología más sencilla y robusta que la propuesta por Wolf hace un siglo y medio. Los resultados [4] fueron sorprendentes ya que las diferencias en la parte histórica de la serie eran verdaderamente notables. Además, destacaba una importante y robusta tendencia creciente en la actividad solar desde la finalización del Mínimo de Maunder (1645-1715) hasta nuestros días. Las diferencias era tan notables entre las dos versiones de la actividad solar de los últimos siglos a partir de observaciones de manchas solares que varios científicos de la comunidad de la física solar y heliosférica propusieron la celebración de varios talleres sobre el “sunspot number” y una revisión completa, resultado de estas reuniones, fue publicada a finales de 2014 [5]. Este último trabajo ha provocado una importante reacción de la comunidad internacional hasta el punto de que un número monográfico de más de 600 páginas de la revista “Solar Physics” ha sido publicado recientemente con trabajos exclusivamente dedicados al “sunspot number” [6]. Entre los logros conseguidos, merece la pena destacar la creación de una nueva colección de observaciones del número de grupos de manchas solares desde 1610 hasta la actualidad con más de un millón de registros [7]. Esta nueva versión del “sunspot number” presenta algunas características que provocan una serie de importantes consecuencias para las ciencias de la atmósfera. Se ha demostrado que la tendencia positiva en la actividad solar que presentaba el “Group Sunspot Number” era un problema de homogeneidad de uno de los observadores primarios de la reconstrucción. Esto modifica notablemente nuestra idea sobre la evolución en los últimos siglos de la irradiancia total solar, un parámetro fundamental para los modelos climáticos. Además, la elección de una nueva escala ha provocado que los números absolutos de la nueva versión sean mayores. Esto puede provocar problemas para los usuarios habituales del “sunspot number” como los científicos que estudian la ionosfera. Este trabajo ha sido parcialmente financiado por la Junta de Extremadura (GR15137) y por el Ministerio de Economía y Competitividad del Gobierno Español (AYA2014-57556-P). Referencias [1] R. Wolf, Mitt. Nat.forsch. Ges. Bern 207 (1851) 89. [2] R. Wolf, Astron. Mitt. Eidgenöss. Sternwarte Zür. 1(I) (1856) 3. [3] J.M. Vaquero, M. Vázquez, The Sun Recorded through History, Spinger, 2009. [4] D.V. Hoyt, K.H. Schatten, Solar Phys. 179 (1998) 189. [5] F. Clette et al., Space Sci. Rev. 186 (2014) 35. [6] F. Clette et al., Solar Phys. 291 (2016) 2479. [7] J.M. Vaquero et al., Solar Phys. 291 (2016) 3061.
        Speaker: Dr. José Manuel Vaquero (Universidad de Extremadura)
      • 16:45
        El proyecto INCITE: Historia de los monzones antes del siglo XX 15m
        El clima monzónico se caracteriza por un cambio estacional en la dirección del viento en niveles bajos asociado a un fuerte contraste entre veranos lluviosos e inviernos secos. Debido al indudable interés socio-económico del monzón para centenares de millones de personas, actualmente se considera esencial disponer de índices que cuantifiquen la intensidad de un monzón para caracterizar con precisión su variabilidad interanual y estimar las posibles tendencias a largo plazo. Existen dos tipos de índices para cuantificar la fuerza de un monzón: los índices dinámicos basados en el viento (normalmente al nivel de 850 hPa) y los termodinámicos basados, en última instancia, en la precipitación. Actualmente las series más largas basadas en viento comienzan a mediados del siglo XX, y utilizan como datos de entrada la componente zonal del viento a 850 hPa obtenida de productos tipo “reanálisis”. Las series basadas en precipitación se pueden remontar hasta los primeros años del siglo XX, cuando las primeras estaciones de medición comenzaron a operar de forma continuada en las principales regiones afectadas por el monzón (África y el Sureste Asiático en particular). Los estudios realizados con estos índices han demostrado que los monzones presentan variabilidad de largo periodo, así como tendencias que en algunos casos son muy significativas, como por ejemplo el debilitamiento del monzón de África Occidental desde la década de 1970 asociado a la sequía en el Sahel. Debido a su gran impacto, la caracterización de la variabilidad de los monzones a largo plazo es esencial, pero es prácticamente imposible encontrar medidas instrumentales de precipitación o viento antes del siglo XX en las regiones directamente afectadas por el monzón. La única medida instrumental registrada de forma sistemática sobre las regiones monzónicas antes del siglo XX es la dirección del viento. Desde hace siglos, miles de navíos han circunnavegado el globo registrando en sus cuadernos de bitácora, diariamente, la dirección observada del viento en la posición del barco. A raíz de numerosos proyectos internacionales, miles de estos cuadernos han sido digitalizados en incorporados a bases de datos digitales [1]. Recientemente, se ha demostrado [2] que es posible construir índices climáticos basados exclusivamente en la dirección del viento (los denominados “índices direccionales”) capaces de caracterizar, de manera muy precisa, los cambios en el trasporte de humedad asociados a la variabilidad estacional del viento. Los monzones pronto se perfilaron como candidatos obvios para ser caracterizados mediante estos índices, y este hecho fue el origen del proyecto INCITE (INstrumental Climatic Indexes. Application to the study of the monsoon-Mediterranean TEleconection), financiado por el Ministerio de Economía y Competitividad en su convocatoria de 2013. Entre los objetivos de INCITE se encontraban el desarrollo de nuevas series instrumentales para caracterizar el monzón de África Occidental [3], el Monzón de la India [4] y el Monzón del Pacífico Occidental, así como investigar su posible conexión con el clima extratropical. Estando próxima la finalización del proyecto, el objetivo de esta presentación consiste en mostrar los fundamentos de los nuevos índices direccionales, su íntima relación con el trasporte de humedad y por tanto, su capacidad para caracterizar la fuerza de un monzón desde mucho antes de que estuvieran disponibles otras series instrumentales. Entre los principales resultados cabe mencionar: 1. La detección de un periodo extremadamente lluvioso en África Occidental a finales del siglo XIX. 2. La posibilidad de localizar la fecha de inicio del Monzón de la India para periodos anteriores al siglo XX. 3. Los cambios en la relación del fenómeno de El Niño con el monzón del Pacífico Occidental a lo largo del siglo XX. 4. Evidencias de inestabilidades en la relación entre el monzón de la India y el clima del Mediterráneo Oriental.
        Speaker: Dr. Gallego David (Universidad Pablo de Olavide)
      • 17:00
        Caracterización de los vientos en Extremadura: un estudio preliminar 15m
        En la actualidad, con el deseo de buscar fuentes de energía no renovables, los datos de viento como variable meteorológica están adquiriendo un valor añadido. El propósito de este trabajo es la caracterización estadística de la velocidad de viento en Extremadura. Para ello, se han utilizado los datos diarios de velocidad media y máxima y dirección de viento registrados desde 1997 hasta la actualidad en 37 estaciones meteorológicas distribuidas en la región. Dichas estaciones pertenecen a la Red de Asesoramiento al Regante de Extremadura (REDAREX). Se ha realizado un estudio estadístico de las series, analizando la distribución espacial de parámetros como: velocidad máxima diaria anual y estacional, velocidad media diaria anual y estacional. También se han estudiado las funciones de distribución de probabilidad de estos valores, siendo la distribución de Weibull aquella a la que mejor se ajustan, y realizado un análisis espacial de los parámetros de dicha distribución en la región. En cuanto a la dirección de viento, se han obtenido las rosas de vientos a partir de los datos de cada observatorio. Este trabajo ha sido parcialmente financiado por la Junta de Extremadura-Fondo Social Europeo (GR15137) y por el Ministerio de Economía y Competitividad del Gobierno Español (AYA2014-57556-P).
        Speaker: Dr. Mª Cruz Gallego (Universidad de Extremadura)
      • 17:15
        Coffee Break 15m
      • 17:30
        Impacto de eventos extremos de pluviosidad en la producción hidroeléctrica en la cuenca Miño-Sil 15m
        En este estudio veremos como afecta el cambio climático a la pluviosidad y a su vez a la producción de energía eléctrica en la cuenca Miño-Sil
        Speaker: Mr. Manuel Fernández González (EphysLab, Universidade de Vigo)
      • 17:45
        Strong signatures of high-latitude blocks and subtropical ridges in winter PM10 in Europe 15m
        En el adjunto
        Speaker: Mr. Jose Garrido-Perez (Universidad Complutense de Madrid (UCM))
      • 18:00
        Estudio de la reproducibilidad computacional del CMIP5 15m
        Trabajo fin de máster que consiste en el estudio de la reproducibilidad computacional de los modelos climáticos que forman parte del CMIP5.
        Speaker: Mr. Michael García (EPhysLab, Universidade de Vigo)
      • 18:15
        Validación de la precipitación en modelos: protocolos y notas metodológicas 15m
        La validación de las salidas de precipitación de los modelos de numéricos de predicción y de los globales de clima/circulación es muy importante para determinar la fidelidad del modelo y su capacidad de capturar la variabilidad climática observada. Siendo la precipitación un campo geofísico de alta variabilidad espacial, y dependiente de un modelado adecuado de la dinámica y la termodinámica, una buena correspondencia con las observaciones es no solo una condición necesaria (aunque no suficiente) para establecer las capacidades del modelo, sino también un buen indicador de calidad. Las validaciones, no obstante, no son triviales, siendo necesario tener en cuenta multitud de detalles de las propias bases de datos de referencia. En esta contribución se analizan algunos aspectos a considerar al respecto, y se ofrece un protocolo de validación.
        Speaker: Dr. Francisco J. Tapiador (UCLM)
        Slides
      • 18:30
        Carroussel de Posters 30m
    • 15:15 19:05
      Quantum Information Aula Química General (Facultad Química (USC))

      Aula Química General

      Facultad Química (USC)

      • 15:15
        Testing fundamentaly binary theories 25m
        Fundamentally binary theories are non-signaling general probabilistic theories in which measurements with many outcomes can always be constructed by selecting from measurements with two outcomes. We show that, for any n, there are quantum correlations between n-outcome measurements which cannot be explained by fundamentally (n-1)-ary theories. Interestingly, even fundamentally binary theories have never been directly falsified by any experiment. Here we report some current theoretical and experimental efforts for falsifying them.
        Speaker: Prof. Adán Cabello (University of Seville)
      • 15:40
        Exact Quantum Change Point Detection 25m
        Sudden changes are ubiquitous in nature. Identifying them is crucial for a number of applications in biology, medicine, and social sciences. Here we take the problem of detecting sudden changes to the quantum domain. We consider a source that emits quantum particles in a default state, until a point where a mutation occurs that causes the source to switch to another state. The problem is then to find out where the change occurred. We determine the maximum probability of correctly identifying the change point, allowing for collective measurements on the whole sequence of particles emitted by the source. Then, we devise online strategies where the particles are measured individually and an answer is provided as soon as a new particle is received. We show that these online strategies substantially underperform the optimal quantum measurement, indicating that quantum sudden changes, although happening locally, are better detected globally.
        Speaker: Dr. Gael Sentis (Naturwissenschaftlich-Technische Fakultät, Universität Siegen, 57068 Siegen, Germany)
      • 16:05
        Entanglement harvesting: entangling systems via local operations 25m
        The abstract contains the overview of the talk that is proposed, as well as an introduction to the subject of matter and the presenter's contributions to the field.
        Speaker: Mr. Alejandro Pozas-Kerstjens (ICFO)
      • 16:30
        Self-testing of multipartite quantum states 25m
        A very timely enterprise nowadays is to understand which states can be self-tested and how. This question has been answered recently in the bipartite case, while it is largely unexplored in the multipartite case, with only a few scattered results, using a variety of different methods: maximal violation of a corresponding Bell inequality, numerical SWAP method, stabilizer self-testing etc. This also explains why it is not clear which states can be self-tested. In our work, we propose a unifying approach: combining projections to two-qubit spaces (projecting parties or degrees of freedom) and then using the maximal violation of tilted CHSH inequalities. In the qubit case, using this simple but general approach, we show that almost all multipartite qubit states can be self-tested (albeit with many measurements), namely all the ones that can be written with all real coefficients in some basis. In particular, this result is enough to characterize the tripartite case completely. Moreover, for special classes of multipartite states, like symmetric Dicke states and graph states, our approach yields a self-test with few measurements. Finally, for the qudit case, we show that all multipartite states which admit a Schmidt decomposition can be self-tested with few measurements
        Speaker: Mr. Ivan Supic (ICFO - Institut de Ciencies Fotoniques)
      • 16:55
        Coffee break 30m
      • 17:25
        Device-independent quantum key distribution with single-photon sources 25m
        This abstract describes a new scheme for Device Independent Quantum Key Distribution, a minimalist form of quantum cryptography in which no modeling is made about the internal working of the devices used. The scheme is appealing as it relies on single-photon sources, a new-generation technology whose development has boosted lately. When physical imperfections are taken into account, our scheme largely outperforms all previous proposals, opening in this manner a promising avenue for experimental DIQKD implementations. This abstract is suited for a talk at the Quantum Information symposium.
        Speaker: Mr. Alejandro Mattar (ICFO - The Institute of Photonic Sciences)
      • 17:50
        Performance evaluation of device-independent quantum key distribution with practical sources 25m
        Device-independent quantum key distribution aims to provide users with information-theoretically secure secret keys without any need for characterizing the physical devices. Nevertheless, there still exists a big gap between theory and experiments. In this work, we evaluate the performance of assisted device independent quantum key distribution in a realistic scenario, that is, using practical photonic sources and a finite number of signals exchanged between the two parties. For this task, we employ recently derived finite key rate formulas against general attacks. Our results are useful to analyze the feasibility of practical device-independent quantum key distribution.
        Speaker: Mr. Víctor Zapatero (EI Telecomunicación, Departamento de Teoría de la Señal y Comunicaciones, Universidad de Vigo, Vigo E-36310, Spain)
      • 18:15
        Classical physics and the bounds of quantum correlations 25m
        The particular set of numerical bounds satisfied by quantum correlations has been intensively studied as a plausible gateway to the first principles of quantum theory, which up to date remain elusive. Here we show that these bounds are indeed not exclusive to quantum theory: for any abstract correlation scenario with compatible measurements, models built on classical waves produce events with probability distributions indistinguishable from those of quantum theory and, therefore, share the same bounds. We demonstrate this finding by implementing classical microwaves that propagate along meter-size transmission-line circuits and reproduce the probabilities of three emblematic quantum experiments [1]. Our results show that the "quantum" bounds would also occur in a classical universe without quanta, where classical fields would be the fundamental physical objects. The implications of this observation will be discussed [2]. [1] D. Frustaglia, J. P. Baltanás, M. C. Velázquez-Ahumada, A. Fernández-Prieto, A. Lujambio, V. Losada, M. J. Freire, and A. Cabello, Phys. Rev. Lett. 116, 250404 (2016). [2] L. Zyga, 'Quantum' bounds not so quantum after all, Phys.org (July 1st, 2016), https://phys.org/news/2016-07-quantum-bounds.html.
        Speaker: Prof. Diego Frustaglia (Universidad de Sevilla)
      • 18:40
        Relativistic physics and beyond with superconducting circuits 25m
        We will discuss several schemes for simulating relativistic motion in superconducting circuit architectures. As a first example, we show how the dynamical modulation of the qubit-field coupling strength in a circuit quantum electrodynamics architecture mimics the motion of the qubit at relativistic speeds. This allows us to propose a realistic experiment to detect microwave photons coming from simulated acceleration radiation [1]. We show that this accelerated radiation can be used to generate entanglement between a pair of qubits [2]. Moreover, we discuss the effects of relativistic motion on single-atom and two-atom Dicke superradiance [2]. Finally, we show that it is possible to simulate effective velocities which even exceed the speed of light in the medium, giving rise to the quantum counterpart of Cerenkov radiation, namely Ginzburg radiation [3]. We propose as well an implementation of a twin-paradox scenario in superconducting circuits, with velocities as large as a few percent of the speed of light [4]. Ultrafast modulation of the boundary conditions for the electromagnetic field in a microwave cavity simulates a clock moving at relativistic speeds. Since our cavity has a finite length, the setup allows us to investigate the role of clock size as well as interesting quantum effects on time dilation. In particular, our theoretical results show that the time dilation increases for larger cavity lengths and is shifted due to quantum particle creation. The combination of both techniques generates a toolbox for studying relativistic phenomena in quantum field theory with superconducting circuits. We will discuss some possible future applications.
        Speaker: Dr. Carlos Sabín (Instituto de Física Fundamental, CSIC)
    • 15:15 20:30
      Thermodynamics Aula Químca Orgánica (Facultad Química (USC))

      Aula Químca Orgánica

      Facultad Química (USC)

      • 15:15
        On the need of Force Field parametrization for a correct description of the host-guest interactions in supramolecular structures that capture and storage CO2 15m
        On the need of Force Field parametrization for a correct description of the host-guest interactions in supramolecular structures that capture and storage CO2 Ángel Vidal-Vidal1*, Carlos Silva López1, and Olalla Nieto Faza2 1 Departamento de Química Orgánica, Facultade de Química, Universidade de Vigo, Campus Lagoas-Marcosende, 36310 Vigo, Spain 2 Departamento de Química Orgánica, Facultade de Ciencias, Universidade de Vigo, Campus As Lagoas, 32004 Ourense, Spain *a.vidal.vidal@uvigo.es Introduction Fast rising of sea level due to ice melting at the Earth's pole or radical changes in terrestrial ecosystems are some of the disastrous consequences that may devastate the globe if human beings are not concerned about contamination and global warming. Excessive amounts of pollutants in the atmosphere is at the root of environmental issues being carbon dioxide (CO2) one of the main greenhouse gases present in the atmosphere [1]. The concentration of this gas in the air has increased by 30% since the 19th century mainly due to intensive use of fossil fuels like coal, oil or natural gas (80% CO2 emissions worldwide) and human activity. Moreover, the International Panel on Climate Change (IPCC) has predicted that CO2 levels in the atmosphere could reach up to 590 ppm by 2100 entailing the rising of almost 2 ºC in the globe [2]. These high values can be obtained in part due to the economic and industrial growth of developing nations, where energy sources with a strong carbon footprint are extensively used. For this reason humans have two challenging issues to address: to find and use a sustainable source of energy and also to reduce greenhouse emissions to achieve environmental protection [3]. At present, CO2 is collected from the atmosphere using absorption processes in which chemical reactions may or may not be involved. The most common procedures are based on the use of basic aqueous solutions of NaOH and KOH or amine scrubbing. The main drawback is the energy that requires, which translates into high economic and environmental cost. Other limiting factors of this technology are the corrosive and environmentally unfriendly character of the reagents involved, the engineering of large and complex absorption units and also the thermal degradation of solvents such amines. The urgency for materials that can be used within CO2 capture has prompted the study of several technologies such as: boron nitride nanotubes, ionic liquids, porous inorganic membranes (PIMs), polymers with light organic functional groups, inorganic-organic interface composites, covalent organic framewoks (COFs), metal organic frameworks (MOFs) and zeolitic imidazolate frameworks (ZIFs) among others tested recently [4]. We use of molecular simulations with the aim of obtaining new compounds that have improved properties over the existing ones such as: high capture capacity, high recyclability, good thermal stability and easy desorption protocols of captured gases if necessary, as well as a high selectivity in the adsoption of certain pollutants. With the aid of computer-aided simulation it is possible to study prior to the synthesis static and dynamical properties such as: the affinity for different gases, capture capacity, isotherms that govern the process, dynamics of the adsoption and time scale and also the ability to identify the degree of occupation of the structure among other properties [5-6]. Bulky solutions of soluble compounds in a specific solvent or extended solids with periodic boundary conditions are often used. Many of the problems that would desirable to tackle with molecular modeling (interesting properties in carbon capture and storage materials) are, unfortunately too large to be studied by means of quantum mechanics since they imply prohibitive computational cost. To deal with this problem, molecular mechanics (MM) is thus invariably used to perform calculations on systems containing a large number of atoms and to simulate systems which the smallest spatial dimension is higher than nanometres [7]. In spite of this, it is necessary to delve deeper into the potentials that are being used in force fields and reparametrize them, if necessary, to obtain a correct description of complex systems such as MOFs, ZIFs, COFs among others. Communication Main Body With the aim of testing the general performance of force fields, DREIDING, AMBER and UFF were selected and compared with high level ab-initio calculations. Among the force fields, we were not able to use the AMBER force field since it does not have parametrized the cumulene carbon of CO2, thus, both UFF and DREIDING have been used to perform calculations using a conventional parametrization and an extra one with charge equilibration on all atoms. The charge equilibration method (QEq) proposed by Rappé et al. That uses as input data experimental atomic ionization potentials, electron affinities, and also atomic radii was used to assign charges to all atoms in both DREIDING and UFF. Some CO2-five-membered-ring heterocycles complexes have been considered for the analysis of the intermolecular interaction potential. Electron-Donor-Acceptor (EDA) complexes between CO2-and heterocycles have been used to analyse the binding energy prediction ability of force fields. Once the inability of the force fields to correctly describe the interactions between CO2 and heterocycles (which are the fundamental links of the structures of the carbon dioxide capture compounds) has been demonstrated, then the study and parametrization of the interaction potentials computed with high-level ab-initio methods is carried out. Two major groups of study will be considered: interaction with the main structure of the heterocycle (carbon skeleton, π-electron density, interaction with the main heteroatom etc.) in different possible configurations and the study of hydrogen bond interactions between CO2 and X-H fragments of the heterocyclic structures. All interaction curves have been parametrized according a Lennard-Jones potential. Acknowledgments The authors thank the Centro de Supercomputación de Galicia (CESGA) for time on HPC infrastructures. Ministerio de Economía y Competitividad (MINECO, CTQ2016-75023-C2-2-P) is also acknowledged for financial support. AVV thank University of Vigo for a predoctoral grant. References [1] R. Monasterky, Nature, 2013, 497, 134-135 [2] C. Change, Synthesis Report, IPCC, 2007 [3] J. Tollefson, Nature, 2011, 473, 134-135 [4] Z. Yuan, Industrial Engineering Research, 2016, 55 (12), 3383-3419 [5] F. A. Cabrales-Navarro, Journal of Membrane Science, 2013, 428, 241-250 [6] S. Amirjalayer Angewante Chemie International Edition, 2007, 46, 463-466 [7] G. A. E. Oxford Industrial & Engineering Chemistry Research, 2010, 49, 10965-10973
        Speaker: Mr. Ángel Vidal Vidal (University of Vigo)
      • 15:30
        Determinación de las propiedades interfaciales líquido-líquido de una mezcla de agua + alcoholes mediante simulación computacional 15m
        El conocimiento preciso de las propiedades interfaciales líquido-líquido de una mezcla acuosa de alcoholes es clave en los de la química, petroquímica e ingeniería ambiental. Las operaciones unitarias de transferencia de masa interfacial como la extracción de líquido o las reacciones químicas interfaciales en ingeniería química, la humectabilidad o la presión capilar en ingeniería petroquímica, o la eliminación de contaminantes en acuíferos y la remediación de las aguas subterráneas en ingeniería ambiental, son sólo unos pocos ejemplos de la importancia y la amplitud de aplicaciones para los cuales el conocimiento de las propiedades interfaciales líquido-líquido juegan un papel fundamental. En este trabajo, se ha empleado la simulación mediante dinámica molecular para predecir las propiedades interfaciales de agua + alcoholes primarios que exhiben un comportamiento con fase inmiscible líquido-líquido. El agua ha sido modelada usando el conocido modelo de agua TIP4P/2005 y los alcoholes (desde el 1-butanol hasta el 1-octanol) han sido descritos usando el modelo TraPPE original. En particular, se ha considerado la dependencia de la temperatura en las propiedades interfaciales más importantes de las mezclas, incluyendo los perfiles de densidad, los diagramas de coexistencia de fases, el espesor interfacial y la tensión interfacial en función de la temperatura a una presión fijada. En este trabajo nos hemos centrado particularmente en la predicción de la tensión interfacial conforme varía la temperatura. La tensión superficial aumenta con la temperatura y alcanza un valor máximo (relacionado con el máximo “tie line” en el equilibrio líquido-líquido). A mayores temperaturas, la tensión interfacial decrece con la temperatura. Además, la tensión superficial aumenta con el peso molecular de las cadenas. En este estudio las predicciones mediante simulación son comparadas con datos experimentales extraídos de la literatura.
        Speaker: Mr. David Amador Luna (Departamento de Ciencias Integradas, Universidad de Huelva)
      • 15:45
        Thermodynamic stability of the size distribution of charged metal nanoparticles 15m
        Ligand-stabilized metal nanoparticles (NPs) have become essential in many active areas of research. A narrow size distribution is essential for controlling their physicochemical properties and for increasing the degree of ordering in NP superlattices. During NP synthesis, coalescence and Ostwald ripening induce polydispersity. Digestive ripening (DR) is a widely-used, post-synthetic step that reduces the dispersity and produces narrow size distributions of ligand-stabilized NPs of noble metals, transition metals, metal sulfides and halides, II-VI semiconductors, lanthanide oxides, as well as alloys and core-shell bimetallic NPs. DR involves heating the as-prepared, polydisperse colloidal solution in the presence of excess strong capping ligand at or near the boiling point of the solvent under reflux. A ligand-exchange reaction induces the redistribution of atoms among NPs and leads to a narrow size distribution. In spite of the experimental efforts to provide insights, the mechanisms of DR are not yet known. We present a DR theory that clarifies the factors that determine the size distribution of charged NPs.
        Speaker: Prof. Jose A. Manzanares (Universidad de Valencia)
        Slides
      • 16:00
        Estudio de las propiedades interfaciales y equilibrio de fases de la mezcla binaria THF+CO2 mediante dinámica molecular 15m
        Introducción El tetrahidrofurano (THF) es un éter cíclico usado ampliamente en la industria como disolvente. Entre sus diversas aplicaciones, el THF puede ser usado como promotor de hidratos [1,2], produciendo el desplazamiento de la curva de coexistencia del hidrato hacia presiones más accesibles. Un hidrato es un compuesto de inclusión cristalino no estequiométrico formado por una red de moléculas enlazadas mediante puentes de hidrógenos formando huecos, en los cuales compuestos de pequeño tamaño y peso molecular (dióxido de carbono, metano, THF, …) pueden ser encapsulados bajo determinadas condiciones termodinámicas. En este trabajo se ha investigado la habilidad de diferentes modelos de THF para predecir el equilibrio de fases y las propiedades interfaciales de sus mezclas con CO2. Por tanto, este trabajo puede ser considerado como un estudio preliminar para el cálculo del equilibrio de fases de los hidratos de THF y de los hidratos de THF y CO2. Este trabajo se centra en la descripción del comportamiento interfacial de la mezcla THF+CO2 a varias presiones y temperaturas. Para ello se han utilizado simulaciones de dinámica molecular y los resultados obtenidos se han comparado con resultados experimentales y teóricos. La ventaja de usar estos tres métodos complementarios, es que mientras que la teoría y la simulación molecular nos permiten estudiar la fenomenología a un nivel atómico de nuestros sistemas, un nivel no accesible experimentalmente, los resultados experimentales nos permiten comprobar la validez de los modelos usados en simulación molecular y de los resultados teóricos. En este estudio se han determinado las propiedades de equilibrio líquido-vapor y las propiedades interfaciales de la mezcla binaria THF+CO2 mediante la técnica de coexistencia directa. Para ello se han realizado simulaciones de dinámica molecular en el colectivo canónico NVT. El THF ha sido modelado usando la aproximación de átomos unidos. Se han usado dos modelos diferentes, el modelo original flexible de TraPPE [3] y una aproximación rígida y plana de este modelo [4]. Las predicciones del equilibrio de fases y de las propiedades termodinámicas de la mezcla binaria obtenidas mediante simulación molecular han sido comparadas con las predicciones obtenidas mediante el formalisto SAFT-VR (Statistical Associating Theory for potentials of Variable Range)[5] y con resultados experimentales[6]. Agradecemos al MINECO la financiación recibida para realizar este trabajo a través de los proyectos con referencias FIS2013-46920-C2-1-P, FIS2015-68910-P y FIS2015-71749-REDT y a la financiación de FONDECYT (Chile) a través del proyecto con referencia 1150656. También agradecemos a la Universidad de Huelva y a la Junta de Andalucía. Jesús Algaba quiere mostrar también su agradecimiento al Ministerio de Educación, Cultura y Deporte por su contrato FPU (Ref. FPU15/03754). Referencias [1] Larsen, R., Knight, C. A., Sloan, E. D., Fluid Phase Equilib. 150 (1998) 353. [2] Sloan, E. D., Koh, C., Clathrate Hydrates of Natural Gases, 3ª ed., CRC Press: Boca Raton, FL, 2008. [3] S. J. Keasler, S. M. Charan, C. D. Wock, I. G. Economou, J.I. Siepmann, J. Phys. Chem. B. 116 (2012) 11234. [4] J. M. Garrido, J. Algaba, J. M. Míguez, B. Mendiboure, A. I. Moreno-Ventas Bravo, M. M. Piñeiro, F. J. Blas, J. Chem. Phys. 114 (2016) 144702. [5] J. M. Míguez, M. M. Piñeiro, J. Algaba, B. Mendiboure, J. P. Torré, F. J. Blas, J. Phys. Chem. B. 119 (2015) 14288. [6] J. M. Garrido, M. Cartes, A. Mejía, J. Algaba, J. M. Míguez, F. J. Blas, A. I. Moreno-Ventas Bravo, M. M. Piñeiro. J. of Supercritical Fluids. (10.1016/j.supflu.2017.04.008)
        Speaker: Mr. Algaba Jesús (Laboratorio de Simulación Molecular y Química Computacional, CIQSO-Centro de Investigación en Química Sostenible y Departamento de Ciencias Integradas, Universidad de Huelva)
      • 16:15
        El papel de las interacciones moleculares en la descripción del equilibrio de fases de los hidratos de CH4 y CO2 15m
        Los clatratos hidratos de gas son redes tridimensionales de moléculas de agua unidas por enlaces de hidrógeno que se forman en condiciones de bajas temperaturas y presiones relativamente altas, formando cavidades bien definidas, dentro de las cuáles, pueden residir moléculas de gases de pequeño tamaño denominadas ‘invitadas’. La enclatración de estas moléculas en el interior de las cavidades permite la formación del hidrato ya que la presencia del gas en su interior estabiliza la estructura del cristal. Las tres estructuras de hidratos más comunes son sI [1], sII [2] y sH [3], que difieren en el tamaño y el número de cavidades que forman la celdilla unidad de cada estructura cristalina macroscópica. El tipo de estructura del hidrato queda determinado principalmente por el tamaño de la partícula invitada, así como, las interacciones entre la molécula invitada y las moléculas de agua que forman la estructura en su inmediato alrededor. La simulación molecular en combinación con la técnica de coexistencia directa de fases se utilizó para predecir la línea de equilibrio trifásico de los hidratos de dióxido de carbono en este trabajo[4]. Se realizaron simulaciones de dinámica molecular en el colectivo isotérmico-isobárico para la determinación de la temperatura de coexistencia trifásica (T3) del sistema dióxido de carbono-agua a presiones en el intervalo de 50-3000 bares. Se investigó la importancia de las interacciones agua-agua y agua-CO2 en la predicción de línea trifásica mediante el uso de los modelos TIP4P/Ice [5] y TIP4P/2005 [6] para el modelado del agua. El modelo TraPPE [7]se utilizó para describir el CO2, y las interacciones agua-CO2 fueron estudiadas a través de la modificación de las reglas de Lorentz-Berthelot que controlan el parámetro de energía cruzado Lennard-Jones entre agua y CO2. Finalmente, toda esta metodología se aplicó al estudio de los hidratos mixtos de CH4+CO2 con el objetivo de estudiar las condiciones óptimas de separación entre el metano y el CO2. En este trabajo el CH4 fue modelado mediante el conocido modelo Lenard –Jones [8] y los resultados obtenidos fueron comparados con los datos experimentales encontrados en la literatura. Agradecimientos A Ministerio de Economía y Competitividad por la financiación del proyecto de investigación (FIS2013-46920-C2-1-P y FIS2015-68910-P). Al CESGA y a MCIA (cluster de la universidad de Burdeos) por permitir el acceso a recursos de computación Referencias [1] D. Metrio, E. Duardo, O. Legario, Nat. Phys. 15 (2019) 735. [1] R. K. McMullan and G. A. Jeffrey, J. Chem. Phys. 42 (1965), 2725. [2]C. W. Mak and R. K. McMullan, J. Chem. Phys. 42 (1965), 2732. [3] J. A. Ripmeester, J. S. Tse, C. I. Ratcliffe, and B. M. Powell, Nature 325 (1987), 135. [4] J. M. Míguez, M. M. Conde, J.-P. Torré, F. J. Blas, M. M. Piñeiro and C. Vega, J. Chem. Phys 142 (2015), 124505. [5] J. L. F. Abascal and C. Vega, J. Chem. Phys. 123 (2005), 234505. [6] J. L. F. Abascal, E. Sanz, R. Garcia Fernandez, and C. Vega, J. Chem. Phys. 122 (2005), 234511. [7] J. J. Potoff and J. I. Siepmann, AIChE J. 47 (2001), 1676. [8] B. Guillot and Y. Guissani, J. Chem. Phys. 99 (1993), 8075.
        Speaker: Mr. Jose Manuel Miguez Diaz (Universidad de Huelva)
      • 16:30
        Simulación molecular de hidratos de metano en condiciones oceánicas 15m
        Los de hidratos de gas (o clatratos de agua) son compuestos de inclusión no estequiométricos constituidos por agua y pequeñas moléculas de gas. Aparecen a bajas temperaturas y presiones moderadamente altas, y están presentes de forma natural principalmente en los fondos oceánicos y el permafrost de las regiones frías [1]. Existen además, evidencias de la presencia de hidratos en cometas y otros cuerpos del sistema solar, especialmente en los planetas exteriores y sus lunas [2], y¬ se considera que abundan en numerosos lugares del universo fuera del sistema solar. Una de las aplicaciones más interesantes de estos compuestos reside en la posibilidad de utilizarlos para capturar contaminantes como clorofluorocarbonos (CFC’s), o el CO2 de origen antropogénico. Otras aplicaciones están relacionadas con su potencial uso para transporte y almacenamiento de gases, ya que la relación existente entre el volumen que ocupa un gas en condiciones normales es 164 veces mayor que el que ocupa formando un hidrato con todas sus cavidades llenas, pero sin el coste que supone mantener un gas altamente comprimido. Actualmente, los hidratos de gas naturales despiertan un gran interés debido a su alto contenido en metano, dadas las implicaciones económicas de este como combustible y su impacto medioambiental como gas de efecto invernadero [3]. A pesar de los numerosos estudios teóricos y computacionales sobre hidratos de gas que existen en la literatura [4,5], no encontramos apenas referencias que incluyan las condiciones oceánicas, en particular la presencia de iones –Na+ y Cl- principalmente-- disueltos en el agua líquida. Es por ello que proponemos y verificamos un modelo molecular para simular el comportamiento de estos sistemas en condiciones más realistas.
        Speaker: Fernández Fernández Ángel Manuel (Universidad de Vigo)
      • 16:45
        Coffee break 30m
      • 17:15
        Uso de materiales alveolares de bajo coste para aumentar la producción de biogás 15m
        Una de las técnicas empleadas para aumentar las poblaciones bacterianas en el interior de los biodigestores anaerobios es utilizar materiales porosos que incrementen la superficie de fijación de aquéllas. Hasta ahora, los materiales utilizados para tal fin han sido diversas arcillas , zeolitas , sepiolita, saponita y bentonita, carbón activado, fibra de caucho. El resultado ha sido un incremento sustancial de las producciones de biogás, pero con un coste económico prohibitivo. En este trabajo se propone el uso de materiales alveolares hechos a medida del residuo orgánico a tratar mediante Digestión Anaerobia (DA), con el fin de aumentar los rendimientos energéticos – y, por tanto, económicos – de la DA, y que, a la vez, sean de bajo coste. Dichos materiales porosos se obtendrán reciclando los siguientes residuos agrícolas y forestales: cáscara de almendra, cáscara de nuez, carbón vegetal y fibras de kenaf. Se concluye que los mayores rendimientos energéticos a largo plazo (para tiempos de reacción superiores a 112 días) se obtienen cuando se usa carbón vegetal como material alveolar, con un incremento de la producción de metano, respecto a la biometanización de la mezcla pura, del 27,82%.
        Speaker: Ms. Consolación Sánchez Sánchez (Universidad de Extremadura)
      • 17:30
        Mejora de la conductividad térmica de líquidos y de sólidos por adición de nanopartículas. Nanofluidos y nanocompuestos 15m
        Ver archivo adjunto.
        Speaker: Dr. JOSE MARIA ORTIZ DE ZARATE LEIRA (UNIVERSIDAD COMPLUTENSE)
      • 17:45
        Densidad hasta 120 MPa y magnitudes derivadas de una polialfaolefina, PAO6 15m
        En este trabajo se ha determinado la densidad a presiones de 0.1 MPa hasta 120 MPa y a temperaturas desde 278.15 hasta 398.15 K de una polialfaolefina, PAO6. Los datos experimentales se han correlacionado con las EoS propuestas por Grzybowski et al., Power-Law Density Scaling (PLDS) y General Density Scaling EoS (GDS) y comparado con los obtenidos con las ecuaciones de Dowson-Higginson y Zhu y Wen. La comparación se extendió a propiedades derivadas de la densidad. Además, se evaluó la capacidad de predicción de las propiedades volumétricas, principalmente la compresibilidad isotérmica, de estas tres EoS hasta 3000 MPa, presión que se puede alcanzar en la lubricación EHL.
        Speaker: Ms. María Jesús García Guimarey (Applied Physics Department, NaFoMat Group)
      • 18:00
        Caracterización termofísica de nanolubricantes basados en grafeno y trioleato de trimetilolpropano 15m
        En esta comunicación hemos caracterizado diferentes propiedades termofísicas (propiedades volumétricas, viscosidades y velocidades del sonido) de dispersiones de nanoplaquetas de grafeno (GnP) en una base lubricante de tipo éster, el trioleato de trimetilolpropano (TMPTO) con la finalidad de analizar el efecto que juegan la concentración de nanopartículas y la temperatura en estas propiedades.
        Speaker: Mr. José Manuel Liñeira del Río (Applied Physics Department, NaFoMat Group)
      • 18:15
        Gold nanoparticles dispersions in PEG 400 for thermal energy storage. Synthesis and physical characterization 15m
        Introduction It is undeniable that the energy and the services that provides are a key issue in the development of the humanity and contribute directly to the well-being of people, among other things. Thus, more specifically, it is crucial to improve the thermal capacities of fluids, since there is a direct relationship between the heat transfer and storage abilities of working fluids and the thermal performance of most installations [1]. Additionally, the flexibility of thermal facilities or the correction of possible unforeseen mismatches between offer and demand can be improved by means of energy storage. A possibility to enhance the efficiency and optimize operating time of those thermal processes is the utilization of functional materials named Phase Change Materials, PCMs, which can storage and release large amounts of latent heat with a slight temperature change [1, 2]. In the last years, new materials with enhanced properties were developed by dispersing particles with high thermal conductivities and nanometric size into these PCMs [3]. Thermal conductivity is the key property in order to improve the charging and discharging mechanisms whereas heat capacity and melting enthalpy allow quantifying both sensible and latent heat storage capabilities. In this work, oleylamine-coated gold nanoparticles were synthesized and dispersed in a polietilenglicol with a low molecular weight to formulate new nano-enhanced phase change materials, NePCMs. The thermal conductivity, heat capacity and enthalpy of these new NePCMs were experimentally determined and the temperature and nanoadditive concentration influences on these physical properties were analysed. Methods ~12nm oleylamine-coated gold nanoparticles were synthesized following a slightly modified procedure already present in the literature [4]. Namely, a solution of 3mL (6.4mmol) of oleylamine and 49mL of toluene was heated to reflux in a 100mL three-neck round-bottom flask and, subsequently, a solution containing 50mg (0.13mmol) of HAuCl4, 1.74mL (3.7mmol) of oleylamine and 1mL of toluene was quickly injected. The reaction mixture was magnetically stirred and refluxed for two hours. The as-synthesized gold nanoparticles were precipitated by adding 50mL of ethanol to the previous mixture and separated via centrifugation (5000rpm, 20min.). In order to remove any undispersed residue, the precipitate was washed three times with ethanol (40mL). Eventually, the black product was dried at 40ºC overnight. All reagents, HAuCl4 (trace metals basis, ≥99.9%), oleylamine (technical grade, 70%) and toluene (ACS reagent, ≥99.5%) were purchased from Sigma-Aldrich and used without further preparation or purification. Absolute ethanol was also used as received. As base material it was used a pharmaceutical-grade polyethylene glycol with an average molecular weight of 400 g/mol, PEG400, supplied by Panreac AppliChem. Purity and molecular weight of PEG were determined through electrospray ionisation mass spectrometry. Thermal stabilities of both gold nanoparticles and PEG400 were studied through thermogravimetric analysis, TGA, with a Setsys 16 TG-DTA (Setaram Instrumentation). NePCMs were prepared following a two-step method by dispersing the dry nanoparticles in the PEG400 with an ultrasonic bath (Ultrasounds, JP Selecta S.A.) working at a frequency of 20 kHz and with a power of 200 W. Temporary stability of dispersions was evaluated by dynamic light scattering technique using a Zetasizer Nano ZS (Malvern Instruments). Thermal conductivity at temperatures from (283 to 323) K was measured using a KD2-Pro (Decagon) device which is based on the well-known transient hot wire technique [5]. Heat capacity was measured in the range between (193 and 313) K with a differential scanning calorimetry, DSC, Q2000 (TA Instruments) equipped with a RSC90 system of cooling and functioning in the quasi-isothermal method (TMDSC) [6]. This last device was also used to analyse the characteristics of (solid - liquid) phase transitions in the temperature range between (193 and 313) K. Results and conclusions Thermal conductivities for both PEG400 and NePCMs decrease smoothly with temperature over the analysed temperature range. A perceptible increase in the thermal conductivity of gold nanoparticle dispersions is already appreciated in relation to base material even for low concentrations. In terms of heat capacity, we have found characteristic behavior in NePCMs in relation to the influence of nanoparticle loading. Figure 1 shows the thermograms obtained for PEG 400 and for the dispersion at 0.1 wt.%, using cooling rates between (1 and 10) K•min-1 and a heating rate of 2 K/min. In this regard, we can underline that the addition of gold nanoparticles may play a role in an easier nucleation during solidification, reducing the temperature range in which fusion happens. References [1] B. Tang, M. Qiu, S. Zhang, Sol. Energ. Mat. Sol. Cells 105 (2012) 242-248. [2] A. Sharma, V.V. Tyagi, C.R. Chen, D. Buddhi, Renew. Sust. Energy Rev. 13 (2009) 318-345. [3] M.A. Kibria, M.R. Anisur, M.H. Mahfuz, R. Saidur, I.H.S.C. Metselaar, Energy Convers. Manage. 95 (2015) 69-89. [4] H. Hiramatsu, F. E. Osterloh, Chem. Mater. 16 (2004) 2509-2511. [5] D. Cabaleiro, J. Nimo, M.J. Pastoriza-Gallego, M.M. Piñeiro, J.L. Legido, L. Lugo, J. Chem. Thermodyn. 83 (2015). 67-76. [6] D. Cabaleiro, C. Gracia-Fernández, J.L. Legido, L. Lugo, Int. J. Heat Mass Transf. 88 (2015) 872-879.
        Speaker: Mr. Marco Antonio Mascos Millán (Departamento de Física Aplicada, Universidade de Vigo, E-36310, Vigo, Spain)
      • 18:30
        Desarrollo de lubricantes basados en nanoaditivos para la producción de energías renovables y uso eficiente de la energía 15m
        Los estudios sobre la estructura y propiedades de las nanopartículas y los nanofluidos han revolucionado diferentes campos de investigación tales como Química-Física, Nanotecnología o Ciencia de materiales, y han permitido desarrollar importantes aplicaciones en la industria, la medicina y la biología. En el caso de los nanofluidos de transferencia térmica y los de almacenamiento térmico se han realizado ya grandes avances. Existeuna red europea que fomenta el uso de estos materiales analizando su eficiencia con el fin de que puedan usarse comercialmente [1]. Otra aplicación de los nanoaditivos en el sector de las energías renovables y uso eficiente de la energía es la de los nanolubricantes. Hay muchos tipos diferentes de nanomateriales con propiedades antifricción y antidesgaste potencialmente interesantes [2]. Los parámetros críticos que influyen en las propiedades tribológicas de los sistemas lubricados a base de nanopartículas son su tamaño, forma y estructura así como la concentración de las mismas. Las investigaciones sobre el uso específico de nanolubricantes en aerogeneradores son muy escasas. Debemos señalar el estudio llevado a cabo por Greco et al. [3] en el que usa una polialolefina aditivada con nanopartículas de nitruro de boro y varios aceros de engranajes con diferentes tratamientos superficiales. Debido a las reacciones triboquímicas entre la superficie y el aditivo del lubricante, se obtienen los mejores resultados con las superficies endurecidas por borización. Existen estudios más generales del efecto de las nanopartículas en lubricación en régimen elastohidrodinámico (EHL), que tiene lugar en engranajes de multiplicadores y en los sistemas de transmisión que se usan en automoción. Ghaednia et al. [4] encontraron buenos resultados con nanopartículas de plata con un tamaño medio de 7 nm en un polietilenglicol (PEG). Moslesh and Shirvani [5] concluyeron que algunos nanolubricantes que contienen nanopartículas de diamante en un aceite de motor, reducen la rugosidad de la superficie de contacto bajo régimen EHL lo cual implica un aumento en la relación de espesor de película y por tanto una menor fuerza de fricción. Los estudios asociados con el uso de nanolubricantes como aceites de motores son muy escasos. Shenderova et al. [6] estudiaron las sinergias entre nanoparticulas de diamante, de teflón y de dialquilditiofosfato de molibdeno en polialfaolifenas y otros aceites. Los tests tribológicos específicos para aceites de motores mostraron reducciones de la fricción desde modestas a significativas dependiendo de las combinaciones de aditivos y aceite. Por ejemplo, el uso de nanodiamantes disminuyó en un 35% las huellas de desgaste.
        Speaker: Dr. María J.P. Comuñas (Universidad de Santiago de Compostela)
      • 18:45
        A Low-Energy Electron Microscope for the Study of Growth and Dynamics of Surfaces in Spain 30m
        Low-energy electron microscopy (LEEM) is a full-view non-scanning technique in which a beam of low-energy electrons that has interacted with a sample is imaged. The technique characterizes the sample's surface in real-space with nanometer-scale lateral resolution. The ability to acquire images at a fraction of a second during temperature changes, while depositing films and exposing materials to reactive gases makes LEEM invaluable for studying dynamical processes on surfaces. The first pure-electron LEEM microscope in Spain is being installed at the Instituto de Química Física “Rocasolano” in Madrid. The goal of this talk is to provide an introduction to the capabilities of this instrument through examples taken from our published work, so it can benefit the spanish research community.
        Speaker: Dr. Juan de la Figuera (Instituto de Quimica Física "Rocasolano")
        Slides
      • 19:15
        Reunión del GET 1h
        Speaker: Prof. José Ramón Solana Quirós (Departamento de Física Aplicada. Universidad de Cantabria)
    • 21:00 22:00
      Reception 1h Salón Noble / Claustro (Colexio Fonseca)

      Salón Noble / Claustro

      Colexio Fonseca

    • 09:00 13:40
      Plenary II Aula Magna

      Aula Magna

      Santiago de Compostela, Facultade de Química

      Av. das Ciencias s/n, 15701 Santiago de Compostela, A Coruña, Spain
      • 09:00
        Transversal Session I. Investigación en Física en España: Implicación en Infraestructuras Cientifico Técnicas Singulares y participación en Organismos Internacionales 1h 40m
        Investigación en Física en España: Implicación en Infraestructuras Cientifico Técnicas Singulares y participación en Organismos Internacionales
        Speakers: Dr. Jose Benlliure (University of Santiago de Compostela), carlos pajares (Professor)
      • 10:40
        Coffee break and poster session 30m
      • 11:10
        Quantum Computations and Quantum Simulations With Trapped Ca+ Ions 50m
        In this talk, the basic toolbox of the Innsbruck quantum information processor based on strings of trapped Ca+ ions will be reviewed. For quantum computation, a scalable Shor algorithm was realized [1] with a string of trapped Ca+ ions. Towards scaling the trapped ion quantum computer, we encode one logical qubit in entangled states distributed over seven trapped-ion qubits. We demonstrate the capability of the code to detect one bit flip, phase flip or a combined error of both, regardless on which of the qubits they occur. Furthermore, we apply combinations of the entire set of logical single-qubit Clifford gates on the encoded qubit to explore its computational capabilities [4]. The quantum toolbox is further applied to carry out both analog and digital quantum simulations. The basic simulation procedure and its application will be discussed for a variety of spin Hamiltonians. Engineered quantum systems offer the opportunity to study emergent phenomena in a precisely controlled and otherwise inaccessible way. We present a spectroscopic technique to study artificial quantum matter and use it for characterizing quasiparticles in a many-body system of trapped atomic ions [5]. Finally, we report the experimental demonstration of a digital quantum simulation of a lattice gauge theory, by realizing (1 + 1)-dimensional quantum electrodynamics (the Schwinger model) on a few-qubit trapped-ion quantum computer [6]. [1] T. Monz et al., Science 351, 1068 (2016). [2] P. Jurcevic et al., Nature 511, 202 (2014). [3] T. Northup and R. Blatt, Nature Photonics 8, 356 (2014). [4] D. Nigg et al., Science 345, 302 (2014). [5] P. Jurcevic et al., Phys. Rev. Lett. 115, 100501 (2015). [6] E. A. Martinez et al., Nature 534, 516 (2016).
        Speaker: Prof. Rainer Blatt
      • 12:00
        Manipulating Relativistic Electrons with Intense Laser Pulses 50m
        In many domains, modern science relies on robust technology, and advanced technology relies on basic fundamental research. Fundamental researches on superconductivity, even if some aspects are not yet fully understood, have conducted to the discovery of many applications such as magnetic resonance imaging or superconducting cavities that are now used in modern accelerators, which have been then successfully used to understand deeply the structure of matter and fundamental interactions. This “virtuous circle” also applied for Laser Plasma Accelerators (LPA). LPA required first powerful laser systems able to deliver stable laser pulses in the few tens of TW to a few PW and, second, the mastering of the giant electric field components with TV/m amplitude [1] in the plasma medium with this well characterized laser pulse. The art of this new area of science relies on our abilities to manipulate relativistic electrons with intense laser pulses.To illustrate the beauty of laser plasma accelerators I will show different experimental results that we recently performed that allow to improve the quality of the electron beam, its stability [2] and its energy gain in longitudinal field [3], or the reduction of its divergence using radial field [4]. I’ll then show how by controlling the quiver motion of relativistic electrons intense and bright X-rays beam are produced in a compact and elegant way [5-7]. Finally I’ll show some examples of applications [8]. [1] V. Malka, Science22, 298 (2002) [2] E. Guillaume et al., Phys. Rev. Lett. 115, 155002 (2015) [3]C. Thaury Scientific Report, 10.1038, srep16310 (2015) [4] C. Thaury et al., Nature Comm. 6, 6860 (2015) [5] K. Ta Phuoc et al., Nature Photonics 6, 308-311 (2012). [6] S. Corde et al., Review of Modern Phys. 85 (2013) [7] I. Andriyash et al., Nature Comm. 5, 4736 (2014) [8] V. Malka et al., Nature Physics. 4, 447 (2008)
        Speaker: Prof. Victor Malka
      • 12:50
        Fire and Ice: The Chicxulub asteroid impact and the K-Pg extinction 50m
        The extinction that marks the end of the Cretaceous period and the beginning of the Paleogene, 66 Ma, is one of the five great extinctions of the Phanerozoic eon. It is estimated that 75-80% of all species became extinct, including all marine dinosaurs and almost all terrestrial dinosaurs. In 1980, Luis Alvarez et al. proposed that the extinction was caused by the impact of a 10-km asteroid; in 1981, Glen Penfield and Antonio Camargo identified the impact crater in the vicinity of the town of Chicxulub, in the Yucatán Peninsula. We present the results of numerical simulations of the consequences of the impact, assuming as an initial condition that the impact produced global fires that injected as much as 70,000 Tg of carbon soot into the atmosphere. The results show that a small part of this soot is entrained into the circulation of the stratosphere and mesosphere, where it remains suspended for a prolonged period, absorbing solar radiation and blocking sunlight at the surface. As a consequence, the Earth’s surface experiences a “global night” lasting 1-2 years, followed by a period of reduced illumination (5-50% of normal) for another 4-5 years. The suppression of sunlight at the surface causes global cooling of about 15°C (10-12° in the oceans and 25-30°C on land). At the same time, the soot in heats the stratosphere, which warms by as much as 100°C. Stratospheric heating affects the chemical composition and photochemistry, such that the ozone layer is reduced globally by 80% of normal, which allows high levels of UV radiation to reach the surface. The combination of darkness, cold, and enhanced UV flux appears to be able to account for the widespread pattern of extinction of Cretaceous flora and fauna.
        Speaker: Prof. Rolando Garcia
    • 13:40 15:00
      Lunch break 1h 20m Campus Vida USC

      Campus Vida USC

    • 15:00 19:00
      Nuclear Physics II Aula Química Física (Facultad Química (USC))

      Aula Química Física

      Facultad Química (USC)

      • 15:00
        The role of Monte Carlo simulations in the radiobiological optimization of proton therapy treatment plans 25m
        The number of facilities offering ion radiation therapy to cancer patients has steadily increased over the last decades, being proton therapy the hadron therapy modality more extended as of today [1]. In general, the main advantage of proton beams, as compared with photon conventional radiotherapy, is related to the shape of the depth dose distribution curves they produce, with a sharp maximum dose known as the Bragg peak. Since the depth of the Bragg peak can be regulated according to the beam nominal energy, each radiation field used in a treatment plan can be energetically adjusted so that its maximum dose is placed within the prescribed tumor volume (PTV). Another important advantage of proton therapy, also with respect to light-ion radiation therapy, corresponds to the exit dose, i.e. the dose deposition in tissues and organs downstream the tumor volume, which is negligible with respect to the dose deposited at beam entrance and at the Bragg peak region. However, the high gradient dose regions produced by proton clinical beams calls for a very accurate modeling of proton propagation through organs and tissues, either as for linear energy transfer (LET) and lateral spread calculations. Especially, it is important to reduce the uncertainties on the value of the mean ionization potential (I-value) in materials relevant for the clinical practice, such as water, to increase the accuracy of LET calculations, and subsequently the beam range calculation in a patient [2]. Furthermore, the radiobiological response of tissues irradiated with protons has been proved to be more complex as compared with photon beam irradiation. Although it is currently established that the relative biological effectiveness (RBE) of protons is 10% larger than mega-voltage photons [3], several models and experimental results have been published recently suggesting a higher RBE value around the Bragg peak region [4]. In this contribution, we show two research activities currently under development by our group within the context described above, in which simulations with the Geant4 Monte Carlo toolkit [5-7] are playing an important role. A first activity aims at providing an accurate I-value for water by means of modeling energy deposition curves measured in water with different light ion beams by Schardt et al. at GSI (Darmstadt, Germany) [8]. Concretely, they obtained the energy deposition as function of the absolute depth in water for protons and ions lighter than 16O, with range values between 5 and 30 cm, approximately; the absolute depth uncertainty reported was 0.2 mm. In our first set of Geant4 simulations, including proton and helium ion beams only, we have obtained a preliminary water I-value of 78.1(5) eV [9], which is compatible with the current I-value recommended by the ICRU, 78(1) eV. A second Monte Carlo activity is focused on the radiobiological description of proton beams, both macroscopically and microscopically. As for macroscopic description of the radiation quality, we have come up with a more reliable strategy to calculate dose-average LET (LETd) distributions in voxelized geometries, since we showed that the most popular scoring approach is subject to bias [10]. This is of importance as for the use of phenomenological radiobiology models found in the literature [11-13]. As for microscopic approach, we are currently producing a set of distributions of microdosimetric stochastic quantities, such as lineal energy (y) and collisional energy imparted (εc), to characterize the radiation quality of the proton beam [14]. We also plan to verify the limits of applicability of a relation proposed by Kellerer between the macroscopic LETd and dose-mean lineal energy (yD) [15]. Finally, our ultimate aim is to compare our calculations with experimental measurements, both at Centro Nacional de Aceleradores (CNA, Seville) and proton therapy centers. This work was funded in part by the Spanish Ministry of Economy, Industry and Competitiveness (under projects no. FPA2014-53290-C2-2-P and FPA2016-77689-C2-1-R) and by Junta de Andalucía (under project no. P12-FQM-1605). The Monte Carlo simulations were performed at our computing cluster FIS-ATOM, hosted at Centro Informático y Científico de Andalucía (CICA, Seville, Spain), whose staff support we gratefully appreciate. References [1] PTCOG web page: https://www.ptcog.ch/ [2] H. Paganetti, Phys. Med. Biol. 57 (2012) R99-R117. [3] ICRU Report No. 78 (2007): “Prescribing, recording and reporting proton-beam therapy”. [4] H. Paganetti, Phys. Med. Biol. 59 (2014) R419-R472. [5] S. Agostinelli et al., Nucl Instrum. Meth. A 506 (2003) 250-303. [6] J. Allison et al., IEEE Trans. Nucl. Sci. 53 (2006) 270-8. [7] J. Allison et al., Nucl. Instrum. Meth. A 835 (2016) 186-225. [8] D. Schardt et al., “Precision Bragg-curve measurements for light-ion beams in water” GSI Scientific Report 2007. [9] A. Perales et al., contribution to ESTRO 36 (2017). [10] M.A. Cortés-Giraldo and A. Carabe, Phys. Med. Biol. 60 (2015) 2645-69. [11] A. Carabe et al., Phys. Med. Biol. 57 (2012) 1159-1172. [12] M. Wedenberg et al., Acta Oncol. 52 (2013) 580-588. [13] A. McNamara et al., Phys. Med. Biol. 60 (2015) 8399-8416. [14] A. Baratto-Roldán et al., contribution to XXXVI Reunión Bienal de la RSEF (2017). [15] A.M. Kellerer, “Fundamentals of microdosimetry”, in: K. R. Kase et al (Eds.), The Dosimetry of Ionizing Radiation, vol. 1, chap. 2. Academic Press Inc (1985).
        Speaker: Dr. Miguel Antonio Cortes-Giraldo (Universidad de Sevilla)
        Slides
      • 15:25
        Simulation of Simultaneous PET Imaging of Antibodies Labeled with Zr-89 and I-124 Based on Triple Coincidences 15m
        Multiplexed PET (mPET) is a new imaging technique able to provide separated images of the biodistribution of two radiotracers based on their standard double coincidences and the triple coincidences generated by one of them. In this work, we evaluated the feasibility of using mPET to improve and facilitate the kinetic analysis of studies with monoclonal antibodies (mAb). By simultaneously administering and imaging mAb labeled with either Zr-89 or I-124, the differences in the activity concentration in the tumor of each isotope can be used to improve tumor detection and the estimation of some of its properties. We have evaluated the proposed method with dynamic realistic simulations of numerical mice phantoms performed with PeneloPET for the preclinical SuperArgus scanner considering all relevant physical effects such as positron emission and annihilation, emission of the prompt gamma rays, and detection in the scanner. The good results demonstrate that this in-silico approach can be used for testing different acquisition protocols before in-vivo acquisitions. It also shows that mPET can be an additional new tool for kinetic modelling of mAb studies.
        Speaker: Dr. Joaquin L. Herraiz (University Complutense of Madrid)
        Slides
      • 15:40
        Medida de producción de isótopos b+ para verificación de rango en protonterapia 15m
        La verificación de la posición del pico de Bragg durante el tratamiento de tumores con haces de protones es uno de los aspectos clave para una mayor eficacia de la protonterapia. Entre las distintas técnicas que se están proponiendo y que ya se están utilizando en pacientes se encuentra la medida de la distribución de núcleos radioactivos + (conocidos como isótopos PET) producidos por el haz de protones a lo largo de su trayectoria, lo cual permite actualmente detectar variaciones de sólo unos pocos milímetros en el rango de haz. En este contexto, es necesario conocer mejor las tasas de producción de varios de estos isotopos (principalmente 11C, 13N y 15O, pero también 30P y 12N entre otros) para Ep=0-230 MeV y una amplia variedad de isótopos y reacciones para los que, aunque hay datos experimentales, se observan diferencias sustanciales. En este sentido se ha comenzado un proyecto para realizar estas medidas y se ha realizado un primer experimento a energías inferiores a 18 MeV en el ciclotrón del Centro Nacional de Aceleradores (CNA), con el plan de realizar medidas adicionales a mayores energías a partir del 2018 en otros aceleradores. En esta contribución se describirán los experimentos realizados hasta la fecha en el CNA y los resultados obtenidos así como los objetivos y planes para medidas a mayores energías.
        Speaker: Dr. Carlos Guerrero (Universidad de Sevilla)
        Slides
      • 15:55
        Performance improvement of MACACO, a Compton telescope for treatment monitoring in hadron therapy. 20m
        La detección de los rayos gamma emitidos por el tejido irradiado constituye una interesante alternativa a las técnicas PET utilizadas en la actualidad para la monitorización del tratamiento en terapia hadrónica. Con esta finalidad, el grupo IRIS del IFIC ha desarrollado un telescopio Compton basado en cristales centelleadores de Bromuro de Lantano acoplados a fotomultiplicadores de silicio (SiPMs). MACACO (Medical Applications CompAct Compton camera) consta de tres planos detectores y ha sido caracterizado tanto en el laboratorio como en pruebas en haz con resultados muy prometedores. Una segunda versión del prototipo ha sido ensamblada recientemente utilizando SiPMs de última generación con el fin de mejorar algunas de las prestaciones del sistema. Los primeros resultados con el nuevo telescopio han supuesto una mejora de la resolución energética de los detectores que se traduce en un aumento de la resolución espacial del sistema. En los próximos meses se realizarán nuevas pruebas en haz.
        Speaker: Dr. Gabriela Llosa (IFIC (CSIC/UV))
        Slides
      • 16:15
        Nuevo método de reconstrucción de mapa de dosis para verificación de técnicas de radioterapia avanzadas a partir de un detector de semiconductor a tiras 15m
        Introducción Las técnicas en radioterapia están en continua evolución. Su objetivo es conseguir una distribución de dosis tal que sea máxima en la zona tumoral y mínima en el tejido sano para evitar efectos secundarios no deseados. El desarrollo de técnicas avanzadas en radioterapia conlleva una mayor complejidad en los tratamientos, lo que hace necesario un desarrollo paralelo de técnicas de verificación dosimétricas. En este trabajo se presenta un novedoso método de reconstrucción de mapa de dosis a partir de la información obtenida por un detector prototipo de tipo semiconductor de tiras de silicio que implica una serie de mejoras sobre el método usado originalmente [1]. Características del detector. Montaje experimental. El prototipo está compuesto por dos detectores de tiras de silicio (en inglés single-sided silicon strip detector SSSSD) de grosor 500μm separados por 500μm de Kapton. Cada detector está dividido en 32 tiras de anchura 2mm y longitud 64mm, rotado uno respecto al otro un ángulo de 90º [2]. Se inserta en el centro de un maniquí cilíndrico de polietileno (de dimensiones típicas de una cabeza) de manera que el plano que define el detector es perpendicular al eje de simetría del cilindro. En general en esta disposición el detector será paralelo a la dirección de los haces de tratamiento. Las medidas corresponderán al plano axial del paciente, que es el plano usado de forma habitual en las imágenes utilizadas en la práctica clínica para especificar la distribución de la dosis que debe recibir el paciente en su tratamiento. Es por tanto el más indicado para realizar la verificación del mismo. En cada franja del detector se colecta la carga liberada por la radiación, que será proporcional a la dosis depositada por la misma en esa área. Una medida correspondiente al detector girado un cierto ángulo respecto a una posición de referencia proporcionará la dosis media en cada tira en esa posición angular. De esta manera, para reconstruir el mapa de dosis completo es necesario tomar medidas en varias posiciones angulares. Gracias a la forma de los dos detectores y que las tiras de ambas forman un ángulo relativo de 90º, para la reconstrucción del mapa de dosis sólo será necesario girar el detector entre 0º y 90º, lo cual reduce el tiempo necesario para la obtención de los datos experimentales para realizar la verificación. Reconstrucción del mapa de dosis En general, los métodos de reconstrucción consisten en obtener una cierta distribución φ a partir de una distribución conocida experimentalmente Φ, siendo conocida también la función que proyecta la primera en la segunda, es decir, Φ = f(φ). Los métodos de resolución pueden clasificarse en dos grupos: métodos analíticos y métodos iterativos. Los métodos analíticos consisten en hallar la función de proyección inversa. Mediante la transformada de Fourier es posible el planteamiento y la resolución del problema en el espacio recíproco, lo que permite el uso de filtros, tratándose así de métodos de retroproyección filtrada. Los métodos iterativos realizan la reconstrucción mediante un bucle cerrado de operaciones. En cada iteración se parte de una distribución dada φo, se proyecta según fobteniéndose Φo y, comparando la proyección obtenida con la experimental Φ, se obtiene una nueva distribución inicial corregida que será el punto de partida de la siguiente iteración. En todo método de iteración están presentes el paso de proyección, que viene definido según el problema físico que se esté tratando, y el paso de comparación-actualización, que no está específicamente determinado pero su elección debería estar fundamentada en modelos relacionados con el sistema de detección para tener una convergencia rápida de la distribución hacia la solución final. En el método analítico, la reconstrucción del mapa de dosis se realiza de forma directa a partir de los datos experimentales [1]. De esta manera, la calidad de la reconstrucción está limitada a la cantidad de información experimental de la que se dispone. Para el detector a tiras, el tamaño mínimo del pixel vendrá dado por el número de posiciones angulares en las que se han tomado medidas. Por otro lado, el posible fallo en la lectura de alguna tira y por tanto el desconocimiento de la dosis asociada, puede dar lugar a huecos en la reconstrucción del mapa. Además el interés clínico requiere que la planificación y verificación de los tratamientos sea lo más rápida posible para agilizar las intervenciones de los pacientes. En este sentido hay que minimizar el tiempo de toma de datos, por lo que la dependencia directa de este tipo de método con las medidas hace necesaria la búsqueda de métodos alternativos. Los métodos iterativos, aunque son comúnmente usados para la reconstrucción de imagen para diagnóstico en el campo de la medicina nuclear, suponen una novedosa técnica en la reconstrucción de mapa de dosis para verificación en el campo de la radioterapia. En este tipo de métodos, los datos experimentales sirven para comparar la proyección de una distribución de partida y corregirla. Como la proyección viene dada por el propio problema físico, puede definirse siempre independientemente de las características con las que se desee reconstruir el mapa de dosis. De esta manera, es posible realizar una reconstrucción completa con una menor dependencia de la cantidad de información que se disponga, además de tener flexibilidad en la forma que la que se realiza la comparación y la corrección. Se muestra un ejemplo de reconstrucción usando el método iterativo (figuras 1b y 1c), a partir de los datos obtenidos con el prototipo descrito anteriormente en el Hospital Universitario Virgen Macarena de Sevilla para un determinado tratamiento. El paso de proyección está relacionado con la contribución de cada pixel a cada tira en cada posición angular. El paso de comparación y actualización se obtiene con métodos de estimación de máxima verosimilitud con una distribución de Poisson para el ruido estadístico [3 y sus referencias]. Este mapa de dosis se compara con el obtenido con el planificador (figura 1a). Referencias [1] M. I. Gallardo et al (2014). “Sistema y método de verificación de tratamientos de radioterapia”. Patente de invención ES 2409760 B1. [2] M.A.G. Alvarez et al (2013). “Novel dual single sided silicon strip detector chip for radiotherapy verification”. Proceedings of Science (X LASNPA) 049:1-6 [3] J.L. Herraiz et al (2006). “FIRST: Fast Iterative Reconstruction Software for (PET) tomography”. Physics in Medicine and Biology 51(18):4547-4565
        Speaker: A. Damián Domínguez Muñoz (Universidad de Sevilla)
        Diapositivas
      • 16:30
        High-Gradient RF laboratory at IFIC for medical applications 15m
        General interest has been shown over the last years for compact and more affordable facilities for hadron-therapy. The High-Gradient (HG) know-how and technology for normal-conducting accelerating RF (Radio-Frequency) electron linac (linear accelerator) structures recently developed for projects such as CLIC (CERN), has raised the achievable accelerating gradient from 20-30 MV/m up to 100-120 MV/m. This gain has come through a better understanding of the high-power RF vacuum arcs or breakdowns (BD) phenomena, the development of quantitative HG RF design methods and refinements in fabrication techniques. This can allow for more compact linacs also for protons, which is potentially important in the new trend in hadron-therapy of using linacs able to provide protons of 70-230 MeV or light ions of 100-400 MeV/u. Linacs are of particular interest for medical applications because they can provide a high degree of flexibility for treatment, such as running at 100-400 Hz pulse rate and pulse-to-pulse beam energy (and intensity) variations. This kind of accelerator is very well suited to treat moving organs with 4D multi-painting spot scanning technique. Project studies like TULIP are taking advantage of these developments and pursuing medical linacs of reduced size. HG operation, which is carried out under ultra-high vacuum conditions (~10-9 mbar), is limited by the BD phenomena and is characterized by the BD-Rate (BDR) or number of BD per pulse and meter. New fresh structures initially operate at a reduced performance and must be conditioned through extended high-power rf operation until the maximum operational gradient is reached. This process is a time consuming, and consequently costly task (> 350 million pulses) which is important to understand and reduce. The IFIC HG-RF laboratory is designed to host a high-power and high-repetition rate facility for testing S-Band (2.9985 GHz) normal-conducting RF structures. This facility will allow the development, RF conditioning and studies of the BD phenomena in HG structures.
        Speaker: Dr. Daniel Esperante Pereira (IFIC - U. de Valencia / CSIC)
        Slides
      • 16:45
        Coffee Break 30m

        Coffee Break

      • 17:15
        Proton minibeam radiation therapy widens the therapeutic window for radioresistant tumors 20m
        Radiotherapy (RT) has a key role in cancer treatment. In fact, about half of the patients will receive RT at some point during their illness. Despite remarkable advancements in RT over the last two decades, significant limitations remain: the tolerance of surrounding normal tissues constitutes a ceiling on tumour doses. In consequence, the treatment of some radioresistant tumours (e.g. gliomas), tumours close to a sensitive structure (e.g. central nervous system) and paediatric cancers is limited. The main challenge in RT is, therefore, to find novel approaches allowing increasing the normal tissue resistance. Along this line we proposed in 2013 a novel concept: proton minibeam radiation therapy (pMBRT) [1]. It allies the physical advantages of protons with the normal tissue preservation observed when irradiated with submillimetric spatially fractionated beams (minibeam radiation therapy) [2]. We have recently implemented the technique [3] at a clinical center (Proton therapy center in Orsay). The technical developments for minibeam generation at a clinical center will be described. The first complete set of dosimetric data in such small proton field sizes was obtained. Due to proton lateral scattering, each proton minibeam of the array (“tooth of the comb”) gets wider as a function of the depth, overlapping at the tumour position. As a consequence, a homogeneous dose distribution is generated inside the tumour (like in conventional RT), while the concept of spatial fractionation (peaks and valleys) and its advantages are maintained in the irradiated regions of normal tissue [1]. See Figure 1. In addition, a negligible dose is deposited in normal tissues after the Bragg peak. We have recently performed a series of in vivo experiments. In the first one the whole brain of 7 weeks old male Fischer 344 rats (n=16) was irradiated with 100 MeV protons. Half of the animals received conventional seamless proton irradiation (25 Gy in one fraction). The other rats were irradiated with pMBRT (58 Gy peak dose in one fraction). The average dose was deposited in both cases. The animals were followed up for 7 months. A magnetic resonance imaging (MRI) follow up at a 7T small animal MRI scanner as well as histological analysis were performed. Rats treated with conventional proton irradiation exhibited severe skin and brain damage. In contrast, the pMBRT group presented neither skin nor significant brain damage. These results indicate that pMBRT leads to an increase in normal tissue resistance. This net gain in normal tissue sparing can open the door to an efficient treatment of very radioresistant tumors, which are currently mostly treated palliatively. In a second experiment we have irradiated glioma (RG2) bearing rats with the same average doses. Long-term survivals have been obtained in the pMBRT group indicating tumor ablation without deleterious side effects. In conclusion, pMBRT widens the therapeutic window for brain tumors, potentially offering a curative option for gliomas, a very aggressive tumor, for which none efficient treatment exists nowadays. Additional experiments are planned in order to corroborate this result. If confirmed, it will pave the way to proceed towards clinical trials at Orsay Proton Therapy Center. This novel technique may specially benefit paediatric oncology (central nervous system whose treatments are very limited due to the risk of complications in the development of the infants). Furthermore, pMBRT is predicted to make proton therapy in general more amenable to administration in either a single dose fraction or in a very small number of fractions, which would significantly reduce the costs. This research was performed with financial support from ITMO Cancer AVIESAN (Alliance Nationale pour les Sciences de la Vie et de la Sante, National Alliance for Life Sciences and Health) within the framework of the Cancer Plan (2014-2019). The authors also acknowledge the calculation time granted at Centre de Calcul de Lyon (IN2P3), at Grand Equipement National de Calcul Intensif (in particular at the supercomputer Curie of CEA), and at Castilla y Le_on Supercomputing Center (Calendula) from the national RES access program (Spanish Supercomputing Network Area) of the MareNostrum Barcelona Supercomputing Center. References [1] Y. Prezado et al. Med. Phys. 40 (2013) 031712. [2] Y. Prezado et al., Rad. Research. 184 (2015) 314. [3] C. Peucelle et al., Med. Phys. 42 (2015) 7108.
        Speaker: Ms. yolanda prezado (IMNC-CNRS)
      • 17:35
        Hybrid Monte Carlo dose calculation for low-energy X-rays Intra-Operative Radiation Therapy. 15m
        In this work we present a dose calculation algorithm that computes dose distributions for low-energy X-rays intra-operative radiation therapy with INTRABEAM within minutes, fully taking into account the different structures of the patient. A detailed validation against Monte Carlo simulations have been performed, and a good agreement (2%-1 mm gamma evaluation) was reached.
        Speaker: Ms. Paula Ibáñez (Grupo de Física Nuclear, Dpto. Física Atómica, Molecular y Nuclear, Facultad de CC. Fïsicas, Universidad Complutense de Madrid, CEI Moncloa, Madrid, Spain)
        Slides
      • 17:50
        Dose average linear energy transfer calculation from microdosimetric quantities with the Geant4 toolkit: Application for proton therapy beams 15m
        Introduction In the last decade, hadrontherapy has gained a great interest in the medical community for its excellent clinical results, leading to the construction and installation of dedicated accelerators in hospital-based clinical centres around the world. Therapy with protons is, by far, the most largely charged particle technique used, having reached a good degree of perfection in clinical practice. However, there is still large space for improvements in what concerns quality assurance and treatment planning verifications. Indeed, protons and heavier ions offer a higher cell-killing effectiveness if compared to photons for a same level of absorbed dose, property that is usually referred to as Relative Biological Effectiveness (RBE). The RBE depends both on radiation quality and on different biological parameters, such as tissue type or endpoint considered, whose knowledge is still limited. Nowadays, a constant RBE value of 1.1 is currently used in radiotherapy treatments with protons, although it is well known that this quantity varies with linear energy transfer (LET), increasing at the distal Bragg peak region [1]. Thus, to take fully advantage of the increasing biological effectiveness of protons, recent studies aim at using dose and dose average LET (Ld) objective functions in treatment planning optimization, working both on LET and dose distributions when optimizing the amount of radiation delivered to the tumour volume [2]. The approach for the calculation of Ld distributions in clinical proton beams may be both based on analytical models or on Monte Carlo simulations. Since most of the Monte Carlo simulations used a very similar method to calculate Ld, whose robustness was not tested for the variation of some critical parameters, in a previous work we decided to address this critical analysis comparing different methods of scoring Ld distributions produced by proton therapy beams in water in a voxelized geometry [3]. Furthermore, in that work we took as reference values for Ld those obtained from microdosimetry calculations according to a formula proposed in [4]. The aim of this work is to further extend the calculations performed in [3], making use of an improved and more efficient code for the calculation of microdosimetric quantities, such as lineal energy and energy imparted per proton electronic collision. Methods and Results In our previous work, in order to determine which Ld scoring method provided more reliable results, we resorted to numerical stability against changes of geometry and production cuts, carrying out the calculations with the Geant4 (GEometry And Tracking) toolkit [5-7]. The resulting simulations, with which we could come up with a robust Ld computation method in good agreement with microdosimetry calculations, were done at central beam axis and for primary protons only. In this work, our goal is to extend to off-axis voxels the calculation of Ld distributions for proton beams in water, including the contribution of secondary protons. To this end, we compared Ld distributions (2D) calculated for clinical proton beams with those computed from microdosimetry spectra obtained for sites of various sizes, whose typical dimension ranged from 0.25 to 10 microns. With respect to our previous work, we implemented a new and more efficient Geant4 application to score microdosimetric quantities, which includes an algorithm capable of randomly place our scoring site in the region occupied by the proton track, including its secondary electrons, as shown in Fig. 1 (left). In doing this, we accounted for electronic equilibrium along the proton track by choosing a world size at least equal to the maximum range of secondary electrons (RMax). In addition, the approach of our new code is suitable to perform calculations with the Geant4-DNA physics package, that simulates step by step interactions of particles in liquid water down to the eV scale [8,9]. Our preliminary results have confirmed the overall validity of our new code. We have also found a slight dependence, with respect to the site size, of the deviations reported between our “macroscopic” calculation of Ld distributions and those obtained from microdosimetry calculations, as emerges in Fig. 1 (right). Acknowledgments This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 675265, OMA - Optimization of Medical Accelerators, and from the Spanish Ministry of Economy and Competitiveness under grand No FPA2016-77689-C2-1-R. The Monte Carlo simulations were carried out at the FIS-ATOM cluster hosted at CICA (Seville, Spain). References [1] T. Matsuura et al., Med. Phys. 37 (2010) 5376-81 [2] N. Bassler et al. Acta Oncol.49 (2010) 1170-76 [3] M. A. Cortés-Giraldo and A. Carabe, Phys. Med. Biol. 60 (2015) 2645-69. [4] A. M. Kellerer, “Fundamentals of microdosimetry”, in: K. R. Kase et al (Eds.), The Dosimetry of Ionizing Radiation, Academic Press INC, 1985, Vol.1, Chap 2. [5] S. Agostinelli et al., Nucl Instrum. Meth. A 506 (2006) 250-303. [6] J. Allison et al., IEEE Trans. Nucl. Sci. 53 (2006) 270-8. [7] J. Allison et al., Nucl. Instrum. Meth. A 835 (2016) 186-225. [8] S. Incerti et al., Med. Phys. 37 (2010) 4692-4708. [9] M. A. Bernal et Al., Phys. Med. 31 (2015) 861-874.
        Speaker: Ms. Anna Baratto-Roldán (Centro Nacional de Aceleradores - Universidad de Sevilla)
        Slides
      • 18:05
        Impact of motion compensation and partial volume correction on 18F-NaF PET/CT imaging of coronary plaque 20m
        Background: Recent studies suggest that 18F-NaF PET enables visualization and quantification of plaque micro-calcification in the coronary tree. However, PET imaging of plaque calcification in the coronary arteries is challenging because of the respiratory and cardiac motion as well as partial volume effects. The objective of this work is to implement an image reconstruction framework, which incorporates compensation for respiratory and/or cardiac motion (MoCo) and partial volume correction (PVC), for cardiac 18F-NaF PET imaging in PET/CT. Materials and methods: Realistic simulations (Biograph TPTV and Biograph mCT) and phantom acquisitions (Biograph mCT) were used. Different uptake values of the plaques (spherical shape, 4 mm diameter) were evaluated in the simulated datasets, with lesion-to-background ratios (LBR) of 10, 20, 50 and 70:1. The experimental phantom included three plaque-type lesions of 18, 31 and 36 mm3 respectively, with a LBR of 70:1. After validation of the MoCo and PVC methods, they were applied to four pilot 18F-NaF PET/CT patient studies. In all cases, the MoCo-based image reconstruction was performed using the STIR software [3]. The PVC was obtained from a local projection (LP) method, previously evaluated in preclinical and clinical PET [4]. We evaluated the noise in the image (measured in a background region) and the lesion-to-background ratio (LBR) values of the plaques, using the maximum (LBRmax) voxel value within the segmented plaque. Results: After applying MoCo and PVC, LBRmax increased by 200% to 1110% in the simulated data, by 212% to 614% in the phantom experiments and by 14% to 188% in the plaques with positive uptake observed in the patients. Similar noise values were observed in all images, in contrast to the significantly higher noise observed when using respiratory or cardiac gating. Conclusion: A combined MoCo and PVC approach for PET/CT imaging was implemented within the STIR reconstruction framework. The simulated datasets, experimental and patient data show significant improvement in the quantification of small coronary lesions when MoCo and PVC are taken into account.
        Speaker: Dr. Jacobo Cal-Gonzalez (QIMP group, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna)
      • 18:05
        Positron Range and prompt-gamma modeling in PET imaging 20m
        Introduction: Besides the conventionally used radionuclides for PET (18F, 11C and 13N), alternative radionuclides such as 68Ga, 124I and 82Rb have been proposed for PET imaging and hundreds of PET radiotracers based on these radionuclides have been developed. Two challenges arise with the use of these radionuclides: their large positron range, which compromises the achievable spatial resolution of the system, and the emission of cascades of gamma-rays in coincidence with positrons, which complicates quantitative PET imaging. In this work we used the Monte Carlo simulation tool PeneloPET developed by our group to model the effects of positron range and prompt emissions in PET image quality. Later, we used this modeling to correct PET images for positron range and prompt gamma emissions effects. Further, a method for improving the quantification of PET images was also implemented and evaluated. Finally, we modified our simulation tool in order to simulate and analyze triple coincidences in PET. Methods: We used PeneloPET to model positron range for different radionuclides in several biological tissues. Positron range (PR) distributions for each radionuclide-tissue combination have been determined and PeneloPET estimations have been compared with previous results found in the literature. In addition, a tissue-dependent and spatially variant positron range correction (TDSV-PRC) method has been developed and evaluated. We have modified PeneloPET to accurately simulate the decay cascades for non-pure emitters of interest for PET imaging, and we implemented and evaluated a local projection (LP) method for partial volume correction (PVC). Finally, we implemented a framework to simulate and analyze triple coincidences in PET. We validated our simulation tool by comparison of our simulated estimations against experimental measurements performed in a modified prototype of the Argus PET/CT scanner. Results: The obtained PeneloPET PR estimations were consistent with previous literature. The TDSV-PRC yields artifact-free reconstructed images for large-PR radionuclides, like 124I or 68Ga, when range corrections are taken into account. The LP-PVC method, together with PRC, provides significant improvement in the quantification of PET images. Good agreement between the simulated and experimental double and triple coincidences spectra was obtained. Conclusion: Monte Carlo simulations may guide the modeling and correction of the main effects that degrade image quality in PET imaging with non-conventional radionuclides.
        Speaker: Dr. Jacobo Cal-Gonzalez (QIMP group, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna)
        Slides
      • 18:25
        ASAMBLEA GEFN 35m
        Speaker: Dr. Dolores Cortina (Universidad Santiago Compostela)
    • 15:00 19:10
      Quantum Materials and Technologies (GEFES) I Aula Química Inorgánica (Facultad Química (USC))

      Aula Química Inorgánica

      Facultad Química (USC)

      • 15:00
        Bending Oxides 30m
        Bending a dielectric material of any symmetry generates polarization thanks to the so-called flexoelectric effect. Conversely, applying a voltage to a dielectric material will cause it to bend spontaneously, due to the converse (or inverse) flexoelectric effect. Both direct and inverse flexoelectricity scale up with the inverse of the thickness of the material, so this phenomenon is gaining prominence with the advent of nanotechnology. On the other hand, and despite its surge in popularity, there have been –until recently- enormous gaps in our knowledge about flexoelectricity, including such fundamental questions as the actual order of magnitude of the intrinsic flexoelectric coefficients, the role of surfaces in the total flexoelectric performance, or even whether flexoelectricity can only happen in insulators. Seeking to answer these questions, the PhD project of Jackeline Narváez has studied the flexoelectricity of single crystals. Her results resolve previous controversies by establishing that (i) the intrinsic flexoelectric coefficients of even the best flexoelectric materials does not exceed a few nC/m; (ii) in relaxors (and some ferroelectrics), there are additional contributions from polar nanodomains that can elevate the total flexoelectric coefficient to the µC/m range; (iii) the contribution of surfaces is at least as big –and sometimes bigger- as intrinsic bulk flexoelectricity and, contrary to previously thought, it is (at least indirectly) measurable, and (iv) semiconductors can also be flexoelectric, and moreover their flexoelectric coefficients can reach the mC/m range; this is one million times more than the intrinsic flexoelectricity of dielectric insulators. In my talk, I will give an overview of the field of flexoelectricity and a summary of the main results (contextualzing their significance) from the PhD thesis of Jackeline Narvaez, ex-aequo winner of the GEFES award to the best thesis in experimental condensed matter physics.
        Speaker: Prof. Gustau Catalan (ICREA and ICN2)
      • 15:30
        On the origin of magnetic anisotropy in two dimensional CrI3 30m
        The observation of ferromagnetic order in a monolayer of CrI 3 has been recently reported, with a Curie temperature of 45 Kelvin and off-plane easy axis. Here we study the origin of magnetic anisotropy, a necessary ingredient to have magnetic order in two dimensions, combining two levels of modeling, density functional calculations and spin model Hamiltonians. We find two different contributions to the magnetic anisotropy of the material, both favoring off-plane magnetization and contributing to open a gap in the spin wave spectrum. First, ferromagnetic super-exchange across the ≃ 90 degree Cr-I-Cr bonds, are anisotropic, due to the spin orbit interaction of the ligand I atoms. Second, a much smaller contribution that comes from the single ion anisotropy of the S = 3/2 Cr atom. Our results permit to establish the XXZ Hamiltonian, with a very small single ion easy axis anisotropy, as the adequate spin model for this system. Using spin wave theory we estimate the Curie temperature and we highlight the essential role played by the gap that magnetic anisotropy induces on the magnon spectrum.
        Speaker: Mr. Jose Lado (International Iberian Nanotechnology Laboratory)
      • 16:00
        Coherent control of nonlinear optical processes in single optical nano-antennas 30m
        Optical nano-antennas have the capability to control the localisation of light on nanometer spatial scales. Coherent control on the other hand, is a technique that often uses femtosecond laser pulses to control light matter-interactions on an ultrafast time scale. Here, we combine ultrafast coherent control with the investigation of nonlinear optical responses in individual plasmonic nano-antennas to demonstrate the simultaneous ultrafast and ultra-small control of light-matter interactions. This work provides a comprehensive study of the ultrafast coherence in optical nano-antennas and how to engineer the phase of ultrashort laser pulses to exploit it for imaging applications.
        Speaker: Dr. Nicolo Accanto (CNRS, Paris Descartes Univerity)
      • 16:30
        Coffee Break and Posters 1h
      • 17:30
        Oxygen vacancies in strained SrTiO3 thin films: formation enthalpy and manipulation 20m
        The control and tune of the cationic and anionic defects formation is a novel route to discover new functional properties in transition metal oxides in general, and particularly in SrTiO3 [1]. STO is a diamagnetic quantum paraelectric insulator, in which oxygen vacancies are typical anionic defects. Due to the donor character of the VO and the very large electron mobilities of these defects, even the slightest concentration of vacancies produces a measurable electrical conductivity. Thus, the presence of VO plays a very important role in the transport properties of STO both in the form of thin films and interfaces, such as the well-studied STO/LaAlO3 interface [2]. Additionally, this heterostructures are subjected to epitaxial strain, which has been shown a remarkable effect in the oxygen vacancy formation enthalpy. For this reason, it is necessary to perform a systematic study of the VO formation energy in STO as a function of strain and understand the influence of these anionic defects in the transport properties of STO. Moreover, the cationic defects, namely strontium vacancies (VSr), also could play a crucial role in the structural properties of the STO thin films [3], producing a characteristic rotation pattern of the TiO6 octahedra to accommodate the coherent epitaxial strain. In this work, we present a complete thermodynamic study of VO formation in e-doped thin films grown by Pulsed Laser Deposition. Hall effect measurements confirmed that each VO is doubly ionized and donates two electrons to the conduction band of STO. Furthermore, our results demonstrate that both, compressive and tensile strain, leads to a decrease in the VO formation enthalpy, in good agreement with the reported ab-initio calculations [4]. On the other hand, we determined the existence of a different rotation pattern of the TiO6 octahedra of the thin films under compressive or tensile strain, which is related with the unintentional presence of the strontium vacancies in the STO thin films. Additionally, we show the possibility to manipulate the oxygen vacancies by applying an external electric field with an Atomic Force Microscopy tip. We demonstrate a change in the local volume and surface potential of the sample associated to the accumulation of oxygen vacancies. The application of a negative (positive) voltage causes a local expansion (contraction) in the surface of the sample about a half or one unit cell height, as can be observed in Figure 1. We also determine the diffusion coefficient of the Vo after removing the electric field as a function of strain, proving that the mechanical effect is stable for hours as well as reversible [5]. References [1] S. V. Kalinin, N. A. Spaldin, Science 341 (2013) 858. [2] A. Ohtomo, H.Y. Hwang, Nature 427 (2004) 123. [3] A. Sarantopoulos, E. Ferreiro-Vila, V. Pardo, C. Magén, M. H. Aguirre, F. Rivadulla, Physical Review Letters 115 (2015) 166801. [4] S. -Y. Choi, S. -D. Kim, M. Choi, H. -S. Lee, J. Ryu, N. Shibata, T. Mizoguchi, E. Tochigi, T. Yamamoto, S. -J. L. Kang, Y. Ikuhara, Nano Letters 15 (2015) 4129. [5] L. Iglesias, A. Sarantopoulos, C. Magén, F. Rivadulla, Physical Review B 95 (2017) 165138.
        Speaker: Ms. Lucía Iglesias (PhD Student)
      • 17:50
        Realization of a Ferroelectric-Domain-Wall Tunnel Junction 20m
        Harnessing the electronic response of ferroelectric thin films may be key in the realization of the visionary concept “The Wall is the Device” [1] towards future non-volatile memories, logic elements or energy-harvesting devices. While extensive work has been devoted to exploit the technological opportunities of the ferroelectric ground state in ultrathin films, and to understand the nature and properties of its domain walls, they have yet to be incorporated into an active device element [2,3]. Here we show results of a magnetic tunnel junction device consisting of a ferroelectric BaTiO3 tunnel barrier just 4.4-nanometer thick, with ferromagnetic La0.7Sr0.3MnO3 electrodes, containing a head-to-head domain wall within its thickness. A confined electron gas is formed at the ferroelectric domain wall, stabilized by oxygen vacancies, which controls the tunneling transport of the magnetic tunnel junction. Resonant tunneling assisted by the discrete levels of the ferroelectric quantum well gives rise to strong quantum oscillations of the tunneling conductance. Our engineered, highly constrained, domain wall provides a major step forward towards exploiting the electronic properties of domain walls for ferroelectric tunnel barriers with new functionalities [4].
        Speaker: Dr. Javier Tornos (Instituto de Ciencia de Materiales Madrid - CSIC)
      • 18:10
        The Magnetochiral effect in Topological Semimetals 20m
        Weyl and Dirac semimetals are topologically nontrivial metallic systems. Many transport and optical properties of these systems display signatures of their nontrivial topological nature, even being dissipative. Here we will demonstrate that Weyl semimetals display a rather exotic response called "magnetochiral effect" appearing in chiral systems under the effect of external magnetic fields. moreover, we will show how the magnetochiral effect shows up in Weyl semimetals in the linear regime in transport quantities, contrary to all the previously cases found in the literature, where the magnetochiral effect appear in the non-linear regime.
        Speaker: Dr. Fernández Cortijo (Instituto de Ciencia de Materiales de Madrid, CSIC)
      • 18:30
        Observation of Large Topologically Trivial Fermi-Arcs in the Candidate Type-II Weyl Semimetal WTe2 20m
        The discovery of non-saturating magnetoresistance and pressure induced superconductivity has drawn much attention to WTe2 lately. [1] The interest on this material increased when it was very recently proposed to be the first example of a new class of materials dubbed type-II Weyl semimetals.[2] The electronic band structure of a type-II Weyl semimetal shows tilted Weyl cones that arise from topologically protected crossings of valence and conduction bands causing touching points between electron and hole pockets near the Fermi level. The projection of these so called Weyl points onto a surface must be connected by Fermi arcs. In WTe2 the surface Fermi arcs terminate inside the bulk electron and hole pockets where the surface states strongly hybridize with bulk states and can no longer be observed experimentally. Additionally, WTe2 is non centro-symmetric, which implies inequivalent top and bottom surfaces with a distinct electronic structure that could not be resolved so far. Together, these subtleties render the identification of the topological nature of the Fermi arcs challenging. We present several advances towards a comprehensive understanding of WTe2 electronic structure. Using micro-focus laser-ARPES we resolve for the first time the distinct electronic structure of both inequivalent top and bottom (001) surfaces. The presence of large surface state Fermi arcs on both surfaces is established. [3] Using surface electronic structure calculations we further demonstrate that these Fermi arcs are topologically trivial and that their existence is independent of the presence of type-II Weyl points in the bulk band structure. Contrary to common believe, the observation of surface state Fermi arcs is thus not suitable to robustly identify a type-II Weyl semimetal. [4] Finally, we show that the bulk Fermi surface is formed by three-dimensional electron and hole pockets with areas that are found to be in good agreement with transport experiments with the exception of small hole pockets that have not been observed in quantum oscillation experiments. This work was supported by the Swiss National Science Foundation through the Ambizione grant (PZ00P2_161327)
        Speaker: Dr. Flavio Bruno (Department of Quantum Matter Physics, University of Geneva, Switzerland.)
      • 18:50
        Light-matter interfacing with quantum dots: a polarization tomography approach 20m
        We report on the polarization tomography of a resonantly-driven quantum-dot cavity-QED device. A single quantum-dot excitonic transition induces a macroscopic rotation on the polarization of the reflected photons, with a polarization purity remaining above 84%.
        Speaker: Dr. Carlos ANTON SOLANAS (Center of Nanosciences and Nanotechnology (C2N), CNRS, University Paris-Sud, University Paris-Saclay, C2N Marcoussis, Marcoussis, France)
    • 15:10 19:20
      Molecular Physics at the Edge I Aula Matemáticas (Facultad de Química (USC))

      Aula Matemáticas

      Facultad de Química (USC)

      • 15:10
        Welcome 5m
        Speakers: José Campos-Martínez (CSIC), Dr. Massimiliano Bartolomei (Instituto de Física Fundamental - CSIC)
      • 15:15
        Theoretical study of the dynamics of superfluid helium nanodroplets doped with alkali atoms 30m
        see attached file
        Speaker: Dr. Nadine HALBERSTADT (CNRS and Université Toulouse III Paul Sabatier)
      • 15:45
        Structure and dynamics of ions in gas phase: interplay between experiments and theory in IRMPD spectroscopy 20m
        IR vibrational spectroscopy is a widespread technique for the characterization of molecules in gas phase, highly sensitive to small structural changes, like hydrogen bonding patterns, thus allowing the detection of motifs and signatures o¬¬ccurring in relevant processes. In the case of gaseous ions, the low density of the sampled species requires the use of a sensitive 'action' spectroscopy approach such as IRMPD (IR Multiple Photon Dissociation) spectroscopy. By this technique the fragmentation due to absorption of multiple IR photons in resonance with active vibrational modes of the molecular ion is probed by mass spectrometry. The IRMPD spectrum is then obtained by reporting photo-fragmentation yield as a function of the IR photon energy. The interpretation of the experimental spectra needs in any case a strong computational support to correctly assign the main features to the corresponding vibrational modes and to identify the populated isomers and/or conformers, particularly when flexible molecule are investigated. This combined approach has recently allowed a comprehensive description at the molecular level for the reactive events responsible for cisplatin activity, including the first direct evidence of a prototypical Eigen-Wilkins encounter complex in solution. The last years have also witnessed increasing applications of IRMPD kinetics experiments, where the use of selected active IR photons can produce selective photo-fragmentation of different isomers or even different conformers, thus enabling the qualitative and quantitative characterization of their population in the experimental mixture.
        Speaker: Prof. Cecilia Coletti (Dipartimento di Farmacia, Università G. d'Annunzio Chieti-Pescara)
      • 16:05
        Laboratory study of inelastic collisions of O2 with He at low temperature 20m
        State-to-state rate coefficients for the inelastic collisions of O2 with He at low temperature are investigated by means of an experimental procedure based on supersonic gas jets probed by Raman spectroscopy. The procedure employs a kinetic master equation (MEQ) which describes the time evolution of the rotational populations of O2 along three supersonic jets of O2 + He mixtures. The MEQ is expressed in terms of experimental quantities (number density and rotational populations), and calculated rate coefficients for the O2:He and O2:O2 inelastic collisions from the literature. By scaling these rate coefficients, a satisfactory agreement with the experiments is accomplished for temperatures between 10 and 34 K.
        Speaker: Dr. José M. Fernández (Instituto de Estructura de la Materia CSIC)
      • 16:25
        Energy transfer in gaseous mixtures for atmospheric and astrochemical modelling 20m
        The development of realistic kinetic models of gaseous systems is a fundamental issue in the study of Earth and planetary atmospheres, plasma chemistry, gas flows and astrochemistry. Particularly, the adoption of a state-to-state level of detail in the description of the molecular energy transfer [1,2], a desirable and necessary improvement, requires much insight into the dynamics of the inelastic collisions and the prompt availability of state-specific energy transfer probabilities and rate coefficients. Existing venerable approximated theories of the energy transfer, such as the Schwartz-Slawsky-Herzfeld one, are not really state-specific and have limited validity. Therefore probabilities and cross sections have to be calculated directly by simulation of the dynamics of the molecular collisions. The reliability of the simulations is conditional to the availability of accurate descriptions of the intermolecular interactions occurring between pairs of the molecular species present in the gas mixture. Here, we present examples of calculation of rate coefficients of energy transfer in mixtures containing CO2 and N2 [3-6] obtained applying a semiempirical approach to the interaction modelling, based on (i) a physically meaningful partition of the contribution to the interaction, (ii) the use of data from molecular beam experiments and (iii) ab initio calculations. An extension of such an approach can be also applied to the modelling dynamics and kinetics of gas-surface systems. Acknowledgments A. L. acknowledges financial support from the Dipartimento di Chimica, Biologia e Biotecnologie dellUniversita di Perugia (FRB, Fondo per la Ricerca di Base), from MIUR PRIN 2010/2011 (contract 2010ERFKXL 002) and from “Fondazione Cassa Risparmio Perugia (Codice Progetto: 2015.0331.021 Ricerca Scientifica e Tecnologica)”. A. L. and F. P. acknowledge the Italian Ministry for Education, University and Research, MIUR, for financial supporting: SIR 2014 “Scientific Independence for young Researchers” (RBSI14U3VF) and financial support from MIUR PRIN 2015 (contract 2015F59J3R 002). References [1] Capitelli, M., Ferreira, C. M., Gordiets, B. F., Osipov, R.: Plasma kinetics in atmospheric gases; Springer Verlag, 2000. [2] E. Kustova, E. Nagnibeda, State-to-state theory of vibrational kinetics and dissociation in three-atomic gases; In Rarefied Gas Dynamics; T. Bartel, M. Gallis, Eds.; AIP Conference Proceedings, Vol. 585, pp. 620–627, IOP Publishing, Bristol, England, 2001. 
[3] M. Bartolomei, F. Pirani, A. Lagana, A. Lombardi, A full dimensional grid empowered simulation of the CO2 + CO2 processes, J. Comput. Chem. 33 (2012) 1806. [4] A. Lombardi, N. Faginas Lago, A. Laganà, F. Pirani, S. Falcinelli, Lecture Notes in Computer Science 7333 Part I (2012) 387. [5] A. Lombardi, N. Faginas-Lago, L. Pacifici, A. Costantini, Modeling of energy transfer from vibrationally excited CO2 molecules: cross sections and probabilities for kinetic modeling of atmospheres, flows, and plasmas, J. Phys. Chem. A 117 (2013) 11430. [6] A. Lombardi, F. Pirani, A. Laganà, M. Bartolomei Energy Transfer Dynamics and Kinetics of Elementary Processes (Promoted) by Gas-Phase CO2-N2 Collisions: Selectivity Control by the Anisotropy of the Interaction 33 J. Comp. Chem. (2016) 1463.
        Speaker: Dr. Andrea Lombardi (Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia)
      • 16:45
        Automated Discovery of Reaction Mechanisms and Kinetics Using Dynamics Simulations 20m
        A novel computational method is proposed in this talk for use in discovering reaction mechanisms and solving the kinetics in reactive systems [1,2]. The method does not rely on either chemical intuition or assumed a priori mechanisms, and it works in a fully automated fashion. It has two components: accelerated chemical dynamics simulations and a post-processing geometry-based algorithm that selects suitable transition state (TS) guess structures. Two levels of electronic structure calculations are involved in the procedure: a low level (LL) is used to integrate the trajectories and to optimize the TSs, and a higher level (HL) is used to refine the structures. Our method has been successfully employed in the study the dissociation channels of formaldehyde, formic acid (FA), vinyl cyanide (VC), propenal, acryloyl chloride (AC), and protonated uracil (uracil-H+), and also in the study the cobalt-catalyzed hydroformylation and hydrogenation of ethylene [3]. Figure 1 shows a flow-chart outlining the different steps of the automated method needed to study organometallic catalysis.
        Speaker: Dr. Emilio Martinez-Nunez (Universidade de Santiago de Compostela)
      • 17:05
        Coffee Break 25m
      • 17:30
        Exploring molecular interactions in the condensed phase with full rotational resolution 30m
        The interaction of molecules determines chemical reactions and biological processes. Very fine details of such interactions can be unravelled using rotational spectroscopy thanks to its great resolving power. However, rotational spectroscopy is usually restricted to the gas phase. In the condensed phases, interactions are usually so strong that rotational features are overshadowed. An exception is liquid helium where interactions are exceptionally weak. Furthermore, its properties are strongly affected by quantum effects. Also, it is an attractive model substance for theory and for experiment: (i) helium atoms, having only two electrons, greatly facilitate high level ab initio calculations of clusters. (ii) At the temperatures where helium becomes liquid all other substances freeze. Liquid helium is therefore one of the purest, if not the purest of all condensed substances. This exceptional purity has recently been exploited for the investigation of nucleation, growth and solidification of nanoparticles [1]. This presentation will highlight two recent experiments where rotational spectroscopy has been pushed to new limits. The full rotational spectrum of a molecular complex was derived using femtosecond wave packet spectroscopy. In another experiment in liquid helium, molecules were identified in their lowest rotational quantum state in thermal equilibrium. Impulsive alignment of clusters in a beam and fluorescence spectroscopy in bulk helium We have excited a supersonic beam of small C2H2-Hen clusters non-resonantly with intense femtosecond laser pulses - a technique called impulsive alignment - thereby creating wave packets composed of rotational eigenstates. The clusters were then probed with a second laser pulse after a set time delay which led to Coulomb explosion. Using the fragment velocity distribution of the C2H2 molecules the state of alignment was determined and the propagation of rotational wave packets was measured in the time domain. A Fourier-transform of the time-spectrum yielded the pure complete rotational spectrum of C2H2-He in excellent agreement with theory [2]. The spectrum showed strong delocalisation of the complex indicating liquid-like character. The excited complex nevertheless rotated coherently over the entire duration of the experiment of 600 ps and showed no signs of dephasing [3]. These results demonstrate that impulsive alignment is well suited to derive structural and dynamical information from clusters, including weakly bound complexes. Production of these complexes requires strong cooling with the consequence that normally only the lowest rotational quantum states are populated. Unlike traditional frequency domain spectroscopy, where selection rules limit the quantum number of states to ΔJ=1, impulsive alignment provides the control that is necessary to excite and probe all J levels, up to the dissociation threshold. In another experiment bulk helium was electronically excited using a corona discharge, creating a rich fluorescence spectrum which was measured as a function of temperature and pressure. Intense fluorescence in the visible region showed the rotationally resolved d u+ b3g transition of He2*. With increasing pressure, the rotational lines merged into single features. The observed pressure dependence of line width, shapes and line shifts established that within liquid helium excimers are either solvated, and cold, or ‘boiling’ within rotationally hot gas pockets. Increase of hydrostatic pressure was found to rotationally cool the excimers at a rate of at least 1010 to 1011 K/s in collisions with the liquids until they occupied the lowest available quantum state [4]. These findings are important with regard to the quest of achieving greatest possible control over molecules, including cooling their degrees of freedom. Also, they suggest that it should be possible to investigate liquid and superfluid helium at the nanoscale over a large pressure and temperature range using molecules as rotational probes. Previous experiments used helium droplets and were therefore restricted to fixed pressures and temperatures. They suggest that by additional control of pressure, temperature and thermodynamic phase unprecedented insight into the structure of solvation layers and interfaces can be achieved. Funding is acknowledged from the Royal Society, The Leverhulme Trust, Erasmus, COST action MOLIM, CONACYT, the Iraq government and the University Joseph Fourier for a visiting professorship for KvH. References [1] H. Gharbi Tarchouna, N. Bonifaci, F. Aitken, L. G. Mendoza-Luna, and K. von Haeften, J. Phys. Chem. Lett. 6 (2015) 3036 [2] G. Galinis, L. G. Mendoza-Luna, M. J. Watkins, C. Cacho, R. T. Chapman, A. M. Ellis, M. Lewerenz, L. G. Mendoza Luna, R. S. Minns, M. Mladenovic, E. Springate, I. C. E. Turcu, M. J. Watkins, L. Kazak, S. Gode, R. Irsig, S. Skruszewicz, J. Tiggesbaumker, K-H. Meiwes-Broer, A. Rouzee, J. G. Underwood, M. Siano and K. von Haeften, Faraday Discuss. 171 (2014) 195 [3] G. Galinis, L. G. Mendoza-Luna, M. J. Watkins, C. Cacho, R. T. Chapman, A. M. Ellis, M. Lewerenz, L. G. Mendoza Luna, R. S. Minns, M. Mladenovic, A. Rouzee, E. Springate, I. C. E. Turcu, M. J. Watkins, and K. von Haeften, Phys Rev. Lett. 113 (2014) 043004 [4] L. G. Mendoza-Luna, N. M. K. Shiltagh, M. J. Watkins, N. Bonifaci, F. Aitken, and K. von Haeften, J. Phys. Chem. Lett. 7 (2016) 4666
        Speaker: Dr. Klaus von Haeften (K-nano)
        Slides
      • 18:00
        Intrinsic Bond Energies: A real space point of view 20m
        A not completely extinguished fire on the nature of the chemical bond in the C2 molecule [1] has re-openened several dormant fronts on the interpretation of bond energies. One of these regards whether we should measure bond strengths with respect to the ground states of the isolated fragments that become bonded, leading to standard bond dissociation energies (BDE), or if appropriately "prepared for bonding", i.e. excited, states should be used instead. The latter view provides larger bond energies, which are usually called intrinsic bond energies (IBE) [2]. Here we examine this problem from a real space partitioning point of view, using the Interacting Quantum Atoms (IQA) approach [3] and electron number distribution functions (EDF) [4]. In IQA, the molecular energy is exactly written as a sum of atomic or fragment self-energies and interatomic (or inter-fragment) interaction energies. The evolution of self-energies along bonding coordinates allows for the identification of the proper atomic/fragment state that reflects the actual electronic state of each fragment in-the-molecule, which can then be used to properly define IBEs. Some results on methane, ethene, ethyne, dinitrogen, and dicarbon will be shown. Acknowledgments We thank the spanish MINECO, grant CTQ2015-65790-P, the FICyT, grant GRUPIN14-049, and the European Union FEDER funds for financial support. References [1] S. Shaik, H. S. Rzepa, R. Hoffmann, Angew. Chemie Intl. Ed , 52. (2013) 3020. [2] D. Cremer, A. Wu, A. Larsson, E. Kraka, J. Mol. Model. 6. (2000) 296 [3] M. A. Blanco, A. Martín Pendás, E. Francisco, J. Chem. Theory Comput. 1 (2005) 1096. [4] E. Francisco, A. Martín Pendás, M. A. Blanco, J. Chem. Phys. 126 (2007) 094102
        Speaker: Prof. Ángel Martín Pendás (Universidad de Oviedo)
      • 18:20
        Continuous spectrum of the H atom after confinement 20m
        The study of confinement effects on atomic and molecular systems has been a topic of recent interest [1]. Experimentally it has been possible to insert atoms and molecules within molecular nanocavities. This brings the possibility of employing such as novel structures for different applications, ranging from energy storage and transport to medical use. In addition, depending on the relative sizes, confinement may exert a strong influence on the electronic structure of the guest atom or molecule. This opens up the field for manipulating the spectroscopic properties of the confined atom, which is of great interest in optics and electronics. In this work we focus in the stability of the atom after it is released from the cavity. If the confined atom or molecule is stored in order to be used to produce energy or to be transported, it is important to analyze if the atom is stable when the confining environment is removed. Here we consider the H atom within an impenetrable spherical wall. This simple model reproduces the most important physical features of confinement and the study of the H atom simplifies the computational problem and the possible excitation mechanisms after the system is released. The excited states of the H atom, both in the discrete and the continuous spectra can be obtained very accurately. We assume that the atom is liberated in a period of time that can be considered small as compared with the dynamics of the atom. Then the sudden approximation can be employed to study the state of the atom after confinement is removed. Within this approach, the time dependent state of the released atom after is expanded in terms of the stationary states of the free Hamiltonian. In this expansion both, the bound states and the Coulomb wave functions need to be included. The linear coefficients provide the amplitude probability of the released atom to reach the corresponding stationary state of the unconfined atom. The values of these coefficients are calculated as the overlap of the confined wave function with the wave function of the unconfined atom. In Table 1 we show the energy of the three stationary states of the H atom here studied. We consider hard wall spherical confinement of radius 2 au with the nucleus of the atom fixed at the center of the wall. In Figure 1 we plot the ionization probability energy distribution of the atom when confinement is released. In all of the cases shown, a spread distribution around a principal maximum is obtained. The value of the energy at the maximum is close and smaller thant the energy of the confined state. The other secondary maxima, obtained at higher energies, are less important. The probability distribution presents several nodes, showing that no electrons with that value of the energy can be emitted. Financial support from the Spanish DGICYT and FEDER, project number FIS2015-69941-C2- 2P, and from the Junta de Andalucía (FQM378) and Universidad de Córdoba is gratefully acknowledged. References [1] K. D. Sen (Editor), Electronic structure of quantum confined atoms and molecules, Springer, Switzerland, 2014.
        Speaker: Dr. Antonio Sarsa (Universidad de Córdoba, Spain)
      • 18:40
        Hydrogen Diffusion along SWCNTs: Time-scale Separation and Tunneling Effects 20m
        The role of nanostructured materials in both fundamental and applied research is ever increasing due to their interesting and unique properties, from catalysis to electronics [1,2]. A specific field of interest is the understanding and development of storage devices for light gases, specially for energy applications (hydrogen) or environmental reasons (CO2, H2S). Carbon nanotubes have been largely studied with the idea of designing possible storage devices for H2 since the late 1990s [3]. However, a complete quantum dynamics description of the diffusion mechanism inside these structures is still lacking. Here we present a quantum mechanical study of the diffusion of the H2 molecule along a narrow (8,0) Single-walled Carbon Nanotube (SWCNT). Following previous works by our group [4] we have modelled the system considering all the degrees of freedom (DOFs, internal and translational) of the hydrogen molecule and a rigid nanostructure.  The cylindrical shape of the potential energy surface, showing five bound DOFs and one unbound DOF, has prompted us to develop an exact diabatization formalism separating two sets of weakly coupled degrees of freedom: on one hand, the unbound coordinate corresponding to the motion of the center of mass of H2 along the nanotube’s axis, and in the other the remaining 5 DOFs, which are effectively confined by the nanostructure. By applying a complete separability assumption to the confined and unbound DOFs we have also developed an adiabatic approximation to the Hamiltonian, which increases the algorithm efficiency while maintaining the accuracy of the results. Both approaches have been employed to simulate Hydrogen diffusion along the SWCNT at temperatures in the 45-135 K range. The computational advantages provided by both method have enabled us to propagate the wave function beyond 15 picoseconds using the State Averaged - MCTDH [5] code, revealing a remarkable resonant structure as well as a noticeable tunnelling effect. Acknowledgments Financial support from the Spanish Ministerio de Economia y Competitividad (CTQ2013-41307-P) and Generalitat de Catalunya (2014- SGR-25) is acknowledged. M.M.-M. further thanks a pre-doctoral grant from the FPU program (FPU2013/02210) from the Spanish Ministerio de Educacioń, Cultura y Deporte. References [1] G. E. Ioannatos and X. E. Verykios, Int. J. Hydrogen Energy 35, 622 (2010). [2] X. Ren, C. Chen, M. Nagatsu, and X. Wang, Chem. Eng. J. 170, 395 (2011). [3] A. C. Dillon, K. M. Jones, T. a. Bekkedahl, C. H. Kiang, D. S. Bethune, and M. J. Heben, Nature 386, 6623 (1997). [4] M. Mondelo-Martell and F. Huarte-Larrañaga, Chem. Phys. 462, 41 (2015). [5] U. Manthe, J. Chem. Phys. 128, 6 (2008). [6] T. X. Nguyen, H. Jobic, S. K. Bhatia, Phys. Rev. Lett. 105 085901 (2010).
        Speaker: Dr. Fermin Huarte-Larrañaga (Universitat de Barcelona)
      • 19:00
        Quantum Nuclear Motion of Helium and Molecular Nitrogen Clusters in Carbon Nanotubes 20m
        High-surface areas and precisely tuned pores of carbon nanotubes make them relevant materials for applications such as in gas adsorption, selective separation of light isotopes, and nanoreactors for quasi one-dimensional confinement of metal nanoparticles. Understanding the role of quantum nuclear effects and intramolecular interactions in the motion of molecules in carbon nanotubes is deeply fundamental. Very recent experimental measurements at low temperatures (2-5 K) of Ohba [1] revealed that much more molecules of nitrogen than helium atoms absorb in small diameter (below 0.7 nm) carbon nanopores, despite of the larger kinetic diameter of the former. Using the helium density functional formulation for a large 4He droplet containing a carbon nanotubes inside, we first show that the experiment can be understood by considering very large zero-point effects in the helium motion, which includes the formation of cavities with zero helium densities [2]. Second, we present an ad-hoc developed nuclear wave-function treatment to provide a detailed insight into the effects of quantum confinement for both N2 and 4He clusters in carbon nanotubes as a function of the tube diameter [3]. Third, we describe our novel pairwise potential model [3] describing the gas adsorption to carbon materials which relies on DFT-based symmetry-adapted perturbation theory. Finally, we propose an embedding approach combining nuclear density functional and wave-function treatments [3]. [1] Ohba , Sci. Rep. 6 (2016) 28992. [2] A. W. Hauser and M. P. de Lara-Castells, . J. Phys. Chem. Lett. 7 (2016) 4929. [3] A. W. Hauser, A. O. Mitrushchenkov, M. P. de Lara-Castells, . J. Phys. Chem. C 121 (2017) 3807.
        Speaker: Dr. MARIA PILAR DE LARA CASTELLS (INSTITUTO DE FISICA FUNDAMENTAL, CSIC)
    • 15:15 20:00
      27º Encuentro Ibérico de Enseñanza de la Física II Aula Biología (Facultad Química (USC))

      Aula Biología

      Facultad Química (USC)

      • 15:15
        Mesa Redonda: Pruebas finales de bachillerato. Las nuevas pruebas LOMCE 1h 15m
        Pruebas finales de bachillerato. Las nuevas pruebas LOMCE
        Speaker: Prof. Luis Hervella (vicepresidente de la CIUG. Universidad de Santiago)
      • 16:30
        Las olimpiadas de física: Preparación de alumnos y Pruebas experimentales 30m
        Las olimpiadas de física: Preparación de alumnos
        Speakers: Carmen Cabanas (IES Eusebio de la Guarda), Óscar Cabeza (Universidade de A Coruña)
      • 17:00
        Coffee break 30m
      • 17:30
        Estudio experimental de la caída de una botella de agua 15m
        Hace unos meses surgió “The Bottle Challenge” y se extendió por medio mundo gracias a youtube [1]. Este método consiste en el lanzamiento de una botella, parcialmente vacía, describiendo una parábola para que ésta caiga de pie (Fig 1). A raíz de este reto, se ha realizado un estudio basado en la observación del movimiento de botellas, lanzadas en diferentes condiciones como semillenas, llenas y congeladas, con el fin de obtener los principales factores que influyen en la caída de la botella
        Speaker: Prof. Luis Manuel Tobaja (Colegio Maria Auxiliadora)
      • 17:45
        Construção de uma Escala de Proficiência do Conhecimento Térmico: TCE Aplicado a Alunos Portugueses 15m
        O instrumento de coleta de dados foi o teste Introdutory Thermal Concept Evaluation (TCE) de autores australianos [1]. O teste possui 26 itens de múltipla escolha e envolve concepções alternativas para o conhecimento térmico. Nos processos de análises preliminares foram utilizados os softwares estatísticos Bilog-MG e o Excel como apoio, seguindo de acordo com o modelo logístico de três parâmetros da Teoria da Resposta ao Item e condições de identificação de itens-âncora. O estudo apresenta resultados preliminares de 2585 alunos do ensino secundário (10º, 11º e 12º ano) da Região Centro de Portugal, em que resulta na elaboração de uma métrica de proficiência diante das concepções térmicas alternativas dos alunos portugueses no respectivo ano de 2014. As perspectivas visam compreender o perfil conceptual diante das dificuldades alunos portugueses e comparar com alunos brasileiros, disponibilizar para a literatura um instrumento avaliativo para comparação e construção de séries históricas de desempenho, evidenciar estabilização de patamares de dificuldades do conhecimento prévio dos alunos, em especial, propor situações-problemas na perspectiva de uma pedagogia de competências.
        Speaker: Prof. Marcel Braga (Universidade de Coimbra)
      • 18:00
        Acercando la nanotecnología al Bachillerato 15m
        La nanotecnología y sus aplicaciones están cada vez más presentes en nuestra vida diaria. Sin embargo, esta rama de la física apenas está representada en el Bachillerato. En este trabajo se presentan problemas relacionados con la nanotecnología que se pueden incluir de forma natural en distintos temas del currículum de esta etapa educativa. Se aportan desarrollos que relacionan de forma sencilla el temario que estudian los alumnos con la investigación en nanociencia. Con ello se pretende reforzar y ampliar sus conocimientos, además de acercarles a un ámbito actual de aplicación de la física. [Abstract completo en el documento adjunto]
        Speaker: Mr. Manuel Alonso Orts (Facultad de CC Físicas, Universidad Complutense de Madrid)
      • 18:15
        Píldoras de Física: una propuesta para compartir recursos entre docentes 15m
        Internet supone una inmensa fuente de recursos y cada profesor va encontrando aquellos que le resultan más eficaces, motivadores o novedosos. Pero en esta profesión a veces tendemos al individualismo y, quizás porque no encontramos ocasión, desperdiciamos ese enorme trabajo que supone buscar y filtrar recursos didácticos que podrían usar muchos más docentes si supieran de su existencia. Con este propósito nacieron las Píldoras de Física (PF) [1], una sección iniciada en diciembre de 2015 a propuesta de la Junta Directiva del Grupo Especializado de Enseñanza de la Física (GEEF), cuyo propósito es abrir una nueva vía de comunicación entre los socios de este grupo, mediante el intercambio de ideas, recursos, metodologías docentes, etc., proyectándolas más allá de las aulas, donde se suelen usar de forma individual. De este modo, se informa al resto de socios del GEEF sobre la existencia de materiales (vídeos, textos, simulaciones, reflexiones…) de interés para la enseñanza de la Física.
        Speaker: Mrs. Ana Blanca (IES Cañada Real. Galapagar. Comunidad de Madrid)
      • 18:30
        La Física en el Bachillerato Internacional: algo más que contenidos 15m
        La Física en el programa del Bachillerato Internacional (IB) pertenece, junto con la Química y la Biología, a las llamadas asignaturas del grupo 4. Todas pueden impartirse a Nivel Medio o bien a Nivel Superior. En todas las asignaturas del grupo, se imparten no sólo contenidos teóricos, sino también el impacto de estas ciencias en la sociedad, dilemas éticos y morales que plantean diversos temas de estas disciplinas y las implicaciones sociales, ambientales y económicas que conllevan. Así mismo, se pone de relieve la importancia de la cooperación y colaboración internacional en todas las materias de este grupo.
        Speaker: Mrs. Consuelo Gajino (15/0086501845)
      • 18:45
        Diseño de una practica de la laboratorio de medición de ozono según el método de Schönbein 15m
        El ozono tropósferico se conoce desde la década de 1830 y nada más descubrir su existencia se inventaron métodos de medida para él por la creencia de que podía poseer cualidades de curación de enfermedades respiratorias. Entre los diversos métodos creados para su medición destaca el desarrollado por Christian Friedrich Schönbein, a quien se le atribuye el descubrimiento del ozono. Este método perfeccionado por otros, destacando al Dr. Berigny y Jame de Sedàn, fue el más usado durante todo el siglo XIX para medir ozono. Aquí presentamos el una práctica de laboratorio fácilmente realizable por alumnos que consiste en la preparación de tiras de medición de ozono, realización de las medidas y verificación de sus resultados. Dicha práctica está parcialmente basada en trabajos previos. Así mismo exponemos como se plantea realizarla en varios institutos de secundaria a lo largo de 2017.
        Speaker: Dr. Añel Juan Antonio (EPhysLab, Universidade de Vigo)
      • 19:00
        Asamblea General GEEF 1h
        Speaker: Prof. Verónica TRICIO (Presidenta GEEG)
    • 15:15 19:05
      Astrophysics II Aula 2.12 (Facultad Química (USC))

      Aula 2.12

      Facultad Química (USC)

      • 15:15
        Discovery of a binary AGN in Mrk 622 25m Aula 2.12

        Aula 2.12

        Facultad Química (USC)

        Mrk622 is a double-peaked narrow emission line galaxy and a dual AGN candidate. New optical long-slit spectroscopic observations clearly show the existence of three spatially separated narrow components in their emission lines, two of them blue and red-shifted respectively with respect to a third one that is found to be at the systemic velocity. The velocity offset between the blue-shifted and the red-shifted components is ∼500 kms−1, and is responsible of the double-peak emission lines. We show that the blue and red-shifted components are produced by two individual AGN. The third systemic component is however a star-bursting galaxy located in the inter AGN region. We thus claim that Mrk 622 is an unresolved, spectroscopically confirmed binary AGN, that harbour a dwarf galaxy in between the pair of AGN.
        Speaker: Prof. Jose Miguel Rodriguez-Espinosa (Instituto de Astrofisica de Canarias)
      • 15:40
        Planetary Nebulae as observed by Gaia: astrometric and photometric expected performance 25m Aula 2.12

        Aula 2.12

        Facultad Química (USC)

        Planetary Nebulae (PNe) are among the most beautiful objects that can ever be observed in the sky with a small size telescope. They present a variety of shapes, from circular, multi-shell, hour glass to butterfly-like, all usually with a high degree of symmetry. They are the irrefutable proof that stars are not immutable objects, but they change with time, they evolve and, often, they have a rapid and certainly showy death. About 90% of the stars in the sky are expected to end their life as PNe, those bright enough to ionize the gas and dust that they expelled while contracting towards the White Dwarf phase, but that are not massive enough to explode as supernovae. PNe are important to understand the chemical evolution of our Galaxy (and also of other galaxies) because they enrich the interstellar medium with products synthetized in the stellar interiors and molecules condensed in the circumstellar shells around their dying bodies. One of the most important problems in current PNe studies is the fact that their distances are poorly known [1]. Paradoxically, these objects are being used as extragalactic distance candles because they are easy to detect and, generally, high luminosity objects. Parallax measurements by the astrometric European satellite Gaia [2] promise to drastically change this situation. In this contribution we review some of the main expected contributions of Gaia data to the study of PNe.
        Speaker: Dr. Minia Manteiga (Universidad de A Coruña)
      • 16:05
        Analysis tool for multi dimension clustering of Gaia Outliers 25m Aula 2.12

        Aula 2.12

        Facultad Química (USC)

        Gaia is one of the key missions of the European Space Agency (ESA), which will conduct a census of the Milky Way with unprecedented accuracy. It is expected to perform observations of an estimated one billion objects, representing roughly 1% of the objects in our Galaxy. It constitutes the biggest amount of data gathered to date and to perform such a task, the Data Processing and Analysis Consortium (DPAC) was organized. It is structured in nine Coordination Units (CU) each one responsible of different tasks related to the processing and management of the data. Our research group is member of the units 8 and 9, in the first one we are developing data mining techniques in order to perform classification of outliers and astrophysical parameter estimations for stars, while in the second one we are developing various tools in order to make data accessible to the scientific community. The purpose of this text is to explain the work that we are doing for the Gaia mission, focusing on the CU9 part, where we have developed a visualization tool useful for the community in order to understand the current classifications of the stars and allowing them to perform its own classifications and analysis of the data.
        Speaker: Mr. Marco A. Alvarez (Universidade de A Coruña)
        Slides
      • 16:30
        The BOOTES worldwide Network of Robotic Telescopes 25m Aula 2.12

        Aula 2.12

        Facultad Química (USC)

        I will show the technological developments implied in the set up of the worldwide BOOTES Network of 60cm robotic telescopes, as well as a summary of the scientific results achieved so far.
        Speaker: Prof. Castro-Tirado Alberto J. (IAA-CSIC)
      • 16:55
        Coffee 30m Aula Magna (Santiago de Compostela, Facultade de Química)

        Aula Magna

        Santiago de Compostela, Facultade de Química

      • 17:25
        Unraveling local Galactic kinematics from the first Gaia data 25m Aula 2.12

        Aula 2.12

        Facultad Química (USC)

        The first Gaia Data Release (Gaia-DR1, 14 September 2016) has set the stage for a profound revolution of galactic astronomy. The first released catalogue, named TGAS (Tycho-Gaia Astrometric Solution), contain parallaxes and proper motions with unprecedented accuracy for about two million well-behaved stars placed in the solar neighborhood. In this talk, we will first review the content of this catalogue in terms of astrometric accuracy and completeness, thus briefly describing the ongoing effort to estimate unbiased distances from parallaxes. Secondly we will discuss, as an example, the TGAS capabilities to undertake new challenges such us the derivation of the dynamical age and place of birth of the Young Local Associations (orbits back on time in realistic Galactic potential). Other recent papers unraveling the first scientific exploitation of Gaia data will be commented.
        Speaker: Dr. Francesca Figueras (Universitat de Barcelona)
      • 17:50
        Formación de hielos de hidrocarburos en Plutón: relación entre superficie y atmósfera. 25m Aula 2.12

        Aula 2.12

        Facultad Química (USC)

        Los datos obtenidos de la misión “New Horizons” han confirmado la presencia de hidrocarburos en la superficie de Plutón. Elementos como metano, etano, eteno y acetileno, se habían propuesto como componentes de dicha superficie a partir de observaciones con diferentes instrumentos terrestres y de simulaciones basadas en datos de laboratorio. A diferencia de otros objetos trans-neptunianos, la formación de etano o eteno en Plutón podría estar relacionada con procesos atmosféricos en lugar de superficiales. Éstos podrían darse en otros objetos como Makemake en el que también se ha demostrado la presencia de estos hidrocarburos. En la charla se analizarán propiedades físicas de estos hielos y las implicaciones de los datos de laboratorio para la interpretación de los datos observacionales y de los modelos
        Speaker: Dr. Miguel Ángel Satorre Aznar (Centro de Tecnologías Físicas (Universitat Politècnica de València))
      • 18:15
        A spectroscopically confirmed rich proto-cluster at z ~6.5 25m Aula 2.12

        Aula 2.12

        Facultad Química (USC)

        We have performed a search for Lyman Alpha sources around two spectroscopically con- firmed star forming sources in the Subaru Deep Field. Deep imaging of this field has resulted in a large number of Lyman Alpha sources potentially related to the two strong star forming sources. Deep GTC/OSIRIS multi-object spectroscopy of a selected sample of these sources has resulted in the spectroscopic detection of at least 4 sources as well as one of the two fiducial sources used as signpost for the observations. At magnitude m = 26AB, these are some of deepest spectroscopically confirmed Lyman alpha sources.
        Speaker: Prof. Jose Miguel Rodriguez Espinosa (Instituto de Astrofísica de Canarias)
      • 18:40
        Efecto de la temperatura en la velocidad de desorción de moléculas. Implicaciones astrofísicas. 25m Aula 2.12

        Aula 2.12

        Facultad Química (USC)

        Para el estudio de la evolución química y física de la materia en el espacio, es crucial comprender los mecanismos de interacción entre fase sólida y gaseosa. Hasta ahora el estudio del proceso de desorción de hielos se ha centrado en la energía de desorción. Ésta se ha relacionado con la interacción entre moléculas en estado sólido, ya sea con la misma especie o con otras. Dicha interacción es fundamental para establecer la temperatura a la cual una molécula determinada se encuentra en estado sólido o gaseoso. La evolución de la materia en el espacio dependerá de los aportes energéticos que sufra, del tiempo que duren dichos aportes energéticos y de la fase, sólida o gaseosa, en la que se encuentre la molécula. La expresión matemática que habitualmente se utiliza para modelar la cinética de la desorción depende de una parte exponencial, donde intervienen la energía y la temperatura de desorción, y una parte pre-exponencial, que depende del número de moléculas, del orden del proceso y de un parámetro denominado factor de frecuencia. En esta comunicación se pretende poner de relieve la importancia del factor pre-exponencial. Cuando una molécula se acerca a la temperatura de desorción máxima, el factor pre-exponencial llega a influir hasta en un orden de magnitud en la velocidad de desorción. Esto hace que su estudio sea crucial en determinados ambientes como en el de formación estelar. Por otra parte, hasta ahora se ha considerado que dicho factor no variaba con la temperatura. La comunicación demostrará la influencia del valor del parámetro pre-exponencial y de la variabilidad con la temperatura a la que se encuentre la molécula estudiada.
        Speaker: Dr. Miguel Ángel Satorre Aznar (Centro de Tecnologías Físicas (Universitat Politècnica de València))
    • 15:15 20:00
      Comunicación y Divulgación Aula 2.11 (Facultad de Química (USC))

      Aula 2.11

      Facultad de Química (USC)

      • 15:55
        Convener: Enrique Arribas 5m
      • 16:00
        Divulgación de la Física de Materiales en Asturias: Nuestras experiencias ante diferentes audiencias 30m
        En esta comunicación presentamos nuestra trayectoria de divulgación de la Física a lo largo de los últimos años en Asturias ante audiencias muy diversas, desde colegios de educación primaria y secundaria hasta centros culturales en pequeñas localidades rurales. Nuestra intención es poner en común nuestras experiencias con los participantes en el simposio y discutir acerca de la importancia de la divulgación y la comunicación para lograr que nuestra sociedad tome conciencia de la necesidad de avanzar en el conocimiento científico para mejorar el bienestar de las personas.
        Speaker: Prof. Pedro Gorria (Universidad de Oviedo)
      • 16:30
        Clubes de ciencias: Estrategia para formar divulgadores y fomentar vocaciones 20m
        La enseñanza de las ciencias como actividad orientada al fomento de las vocaciones científicas y a la educación científica, contribuye a la formación de ciudadanos críticos. La divulgación científica es una tarea de suma importancia tanto para docentes como investigadores, se realiza a través de diversos medios de divulgación, como lo son los talleres, publicaciones y ferias de ciencias. Una vía de divulgación es la formación que reciben niños y jóvenes dentro de los clubes de ciencias. Durante su estancia en estos centros de formación, los participantes logran desarrollar un conocimiento, siguiendo un procedimiento de investigación formal adecuado a su edad, que se completa con la presentación de resultados en diversos foros, entre ellos las ferias de ciencias.
        Speaker: Ms. Raquel Ramirez-Vazquez (UCLM)
      • 16:50
        La física desde el punto de vista del estudiante de grado 20m
        La física desde el punto de vista del estudiante de grado J. Joaquín Pérez Maciá1, A. Catalán Benavent2 1 jojopema@alumni.uv.es 2 acabe6@alumni.uv.es Facultad de Física, Universitat de València, Burjassot 46100, Spain Introducción En esta presentación deseamos reflejar las experiencias, y las opiniones, que hemos tanto vivido como escuchado y observado a lo largo de nuestros estudios del grado en Física de la Universidad de Valencia. Ver las dificultades con las que te topas en el paso de bachillerato a la universidad, y la necesidad de, entre otras materias, haber dado algo de álgebra en bachillerato. También queremos hablar de cómo conforme vas avanzando cursos, la carrera gana belleza, donde vas pasando de dar por encima toda la física, a profundizar en electromagnetismo, óptica, cuántica, etc. Otro de los objetivos es reflejar cómo el número de horas de trabajo en algunas asignaturas, no se ve reflejado en el número de ECTS que recibes por cursarlas. Finalmente, hablamos de lo poco valorada que está la docencia en la universidad frente a la investigación, desde nuestro punto de vista como estudiantes. Nuestra experiencia personal ¿Cómo de bien preparados terminamos un bachillerato de ciencias? A lo largo del bachillerato, y hablando únicamente de física y matemáticas, salimos sabiendo integrar, derivar y resolver matrices, en cuanto a las matemáticas, y sabiendo acerca de tiros parabólicos, cinemática y, en menor cantidad, óptica, electromagnetismo y gravitación, en cuanto a física. Empezamos la universidad y nos topamos con que nunca hemos pisado un laboratorio de física, o con que hay conceptos en los que hemos profundizado demasiado y en otros, en cambio, muy poco. No consideramos que salgamos mal preparados, pero, ¿salimos todo lo bien preparados que podríamos salir? Al margen de lo explicado, nos centraremos concretamente, como un ejemplo particular, en que si quieres estudiar física, hace falta ver más álgebra en bachillerato. Acabas el instituto sabiendo integrar de cien formas diferentes, pero sin tener ni idea de álgebra más que una base de números complejos. Llegas al primer curso del grado y empiezas a darla, en un año te dan muchos conceptos, que te fascinan y a la vez te aterrorizan, porque es totalmente nuevo y te cuesta trabajo entenderlo, aunque acaba siendo una de las asignaturas que más gusta (también de más suspensos), qué pena no haber visto las matemáticas de esta manera antes. Después te dejan tablas y tablas de integrales a lo largo de la carrera y, en cambio, te topas con cuántica sin recordar bien lo que era un operador, o lo que es un tensor, dado que solamente lo has trabajado durante un curso, y con muy poca aplicación en la física. Conforme vamos avanzando cursos, y vamos dejando atrás ese primer año de adaptación, de más matemáticas que física, de más física clásica que “moderna” y de asignaturas comunes a todas las ciencias, que no son especialmente vitales para nuestro futuro laboral, por lo menos no los conceptos que nos enseñan, comenzamos a ver esa física que tantas ganas teníamos de aprender: empezamos a ver cómo evolucionan las estrellas, los misterios de la física cuántica, la parte electromagnética de la óptica (y no sólo espejos y lentes), o la verdadera complejidad del átomo y de su núcleo formado por protones y neutrones. Aun así, nadie dijo que el camino fuera fácil, pero, una cosa es que no sea fácil, y otra es que no sea lo que supuestamente ha de ser. Con esto pretendemos decir que el esfuerzo en una asignatura, con un número de créditos determinado (en la cual cada crédito corresponde a un número de horas de trabajo) no siempre se corresponde con lo que supuestamente debería ser. Esto, entre otras cosas, es debido al paso de licenciatura a grado, algunas asignaturas que están consideradas de 5 créditos, como en general los laboratorios, ocupan mucho más tiempo que otras consideradas de más créditos, ya que suelen ser sesiones de una mañana entera (4-5 horas) y luego todavía te queda bastante trabajo para casa, hay que analizar resultados, hacer memorias, y llevar una buena libreta, todo esto conlleva tiempo, mucho más del que se piensa. Finalmente nos gustaría hablar del poco valor que, según nuestra apreciación como estudiantes, se da a la docencia frente a la investigación, parece que para algunos profesores dar clase sea simplemente el precio que tienen que pagar si quieren investigar, y quien pierde en estos casos son los alumnos. Si las encuestas de evaluación verdaderamente se tuvieran en cuenta, probablemente a los estudiantes se nos formaría mejor. No motiva mucho estudiar una asignatura, y mucho menos asistir a clase, cuando tu profesor se dedica a sentarse y a leer diapositivas, que son un buen recurso, pero hay que saber emplearlo, o cuando se dedica a copiar en la pizarra apuntes sin siquiera pararse a explicarlos. En cambio, también está la cara opuesta, cuando el profesor consigue que una hora de clase se te pase en cinco minutos, cuando ofrece un horario de tutorías amplio y abierto a cambios, el que nos sube todo tipo de material al aula virtual, en resumen, el que se preocupa por enseñar, al que le importan los alumnos y su formación. Es precisamente en esas asignaturas donde el esfuerzo del profesor se ve reflejado en la nota de los alumnos y donde los alumnos realmente aprenden y se enamoran aún más de la física. Para una mayor visión sobre concretamente este último punto párrafo: http://www.uv.es/~azcarrag/pdf/2015%20CIAN%20Bolonia%203+2%20vs.%204+1.pdf Referencias [1] www.uv.es\fisica [2] J. A. Azcárraga http://www.uv.es/~azcarrag
        Speakers: Ms. Ana Catalán Benavent (Universidad de Valencia), Mr. Jose Joaquín Pérez Maciá (Universidad de Valencia)
      • 17:10
        Coffee break 30m
      • 17:40
        Divulgando la Ciencia a través de la Radio 20m
        Presentamos una experiencia de divulgación de la Ciencia basada en la utilización de una emisora de radio como vehículo. Cuando acaba la programación nacional de la Cadena SER (Sociedad Española de Radiodifusión) a las 12:30 de cada día laborable, comienzan las programaciones locales que suelen cubrir hasta las 14:00, hora en la que empiezan las noticias nacionales. Dentro de esa programación local de la Cadena SER en la provincia de Albacete, los jueves a una hora indefinida entre las 13:30 y las 14:00 se emite el programa “Conciencia” que coordino.El programa comienza con los acordes de la canción “We Will Rock You” de Brian Harold May, músico británico y doctor en astrofísica, muy conocido por ser el guitarrista de la famosa banda británica Queen. La sección “Conciencia” tiene una duración aproximada de 12-14 minutos y lleva en antena desde el 8 de enero de 2015, coincidiendo con el año internacional de la luz.
        Speaker: Prof. Enrique Arribas (Castilla-La Mancha)
      • 18:00
        Campos Electromagnéticos de Radiofrecuencia y cáncer de causas inespecíficas 30m
        Se presentan los resultados de un estudio epidemiológico en el que se analizó la correlación entre la exposición a RF-EMF en la ciudad de Albacete (166.000 habitantes) y la incidencia de algunos cánceres de causas inespecíficas (linfomas y tumores cerebrales). Para ello, se analizó la exposición personal a los EMF-RF en las diferentes secciones censales de la ciudad de Albacete; se elaboró un mapa de exposición de las personas a los EMF-RF, mediante datos agregados, de la ciudad de Albacete; se estudió la posible relación entre el mapa de exposición a los EMF-RF y la ubicación de las antenas de telefonía en la ciudad de Albacete; y finalmente, mediante análisis de datos espaciales (patrones espaciales de puntos y datos agregados) se estudió la distribución y posible aleatoriedad de los casos de tumores cerebrales registrados, para analizar si existe una relación causa efecto entre los EMF-RF y dichos tumores
        Speaker: Ms. Raquel Ramirez-Vazquez (UCLM)
      • 18:30
        Instalaciones científicas singulares en España con investigación en Física 25m
        El objetivo de esta comunicación es presentar las principales instalaciones tecnocientíficas en territorio español relacionadas con la física, incluyendo, desde un punto de vista general, las diferentes líneas de investigación asociadas. En particular está enfocada para su uso por profesores de enseñanza secundaria y de universidad (principalmente para Bachillerato y primeros cursos de Ciencias Físicas), con el fin de facilitar la realización de proyectos de intervención educativa asociados al objetivo indicado. El objetivo final es fomentar tanto la vocación científica entre los alumnos de secundaria como la investigadora en los universitarios.
        Speaker: Dr. Soler Ferran Pablo (RSEF)
    • 15:15 19:15
      Energy and Sustainability II: Workshop GEES-CIEMAT Aula Física (Facultad de Química (USC))

      Aula Física

      Facultad de Química (USC)

      • 15:15
        WORKSHOP ALTA INTEGRACIÓN DE RENOVABLES EN SISTEMA ELECTRICO. ALMACENAMIENTO ENERGIAS DE APOYO. ESCENARIOS 2030‐2014 1h 45m
      • 17:00
        Coffee Break 30m
      • 17:30
        MESA REDONDA. ALTA INTEGRACION DE RENOVABLES EN SISTEMA ELECTRICO ESPAÑOL. ESCENARIOS (2030‐2040) 1h 45m
    • 15:15 19:15
      Física Médica I Aula Química Física (Facultad de Química (USC))

      Aula Química Física

      Facultad de Química (USC)

      • 15:15
        Join Session with Nuclear Physicss 4h Aula Física (Santiago de Compostela, Facultade de Química)

        Aula Física

        Santiago de Compostela, Facultade de Química

        Same as Nuclear Physics II
    • 15:15 18:15
      Particle and Theoretical Physics I Aula Química Técnica (Facultad de Química (USC))

      Aula Química Técnica

      Facultad de Química (USC)

      Conveners: Dr. Isidro González Caballero (Universidad de Oviedo), Dr. JOSE SALT (IFIC), Dr. Santiago Gonzalez de la Hoz (IFIC)
      • 15:15
        Enhancement of the relic neutrino density in the Milky Way 30m
        Neutrino oscillations have shown that these weakly interacting particles have a mass different from zero, although cosmology points towards smaller values for their masses than previously expected. Despite the smallness of their mass, relic neutrinos coming from the time of their decoupling might cluster under strong gravitational potentials, such as the one of our galaxy, leading to an overdensity of such neutrinos in our surroundings. This can be helpful for future experiments' aiming at detecting relic neutrinos, like PTOLEMY. I will discuss an update on the gravitational clustering of relic neutrinos in the Milky Way, showing that the expected overdensity is unfortunately lower than desired.
        Speaker: Mr. Pablo Fernández de Salas (IFIC)
        Slides
      • 15:45
        Latest improvements on nPDFs 30m
        I will review the current status of the DGLAP global analysis of nuclear parton distribution functions, nPDFs. Th different nPDF sets available will be presented, focusing on the latest improvements and the next steps to be made.
        Speaker: Carlota Andrés Casas (USC)
        Slides
      • 16:15
        Search for electroweak SUSY production in the CMS experiment 30m
        The measurements described in this contribution aim to study the SUSY model cases where the lightest fermionic superpartners of the SM bosons (namely, charginos and neutralinos) appear via electroweak production where the final state contains multiple leptonic particles. As many searches that target similar final states are being developed a combination effort is being developed that will be also touched in this talk.
        Speaker: Mr. Carlos Francisco Erice (Universidad de Oviedo)
      • 16:45
        LHCb: A general purpose detector in the forward region 30m
        - Introduction Located in Geneva (Switzerland), LHCb is one of the 4 big detectors of the Large Hadron Collider (LHC), the largest particle accelerator in the world, in which proton-proton collisions have been taking place since 2009 at different unprecedented energies. LHCb is a forward spectrometer whose acceptance and specific features makes it very complementary to the rest of the LHC experiments. LHCb has been able to produce many interesting measurements so far that have turned out to be very important to understand the composition and nature of matter at the most elemental scales. Examples of very well known results concerning flavor physics and spectroscopy are the first observation of the Bs→μμ decay [1], the measurement of the CP-violating phase ϕs [2] or the observation of J/ψp resonances consistent with pentaquark states [3]. However, in the last years, LHCb has been able to make relevant contributions in many other areas beyond those for which it was originally designed, a summary of which will be presented in this talk. More specifically, focus will be set on newest results and in those areas in which the author has worked more actively. These and many other results make LHCb currently a general purpose detector in the forward region. - Direct searches for light particles Several New Physics (NP) models predict the existence of particles beyond those of the Standard Model (SM) for whose detection LHCb is particularly well suited. The main reason for this is a flexible trigger, significantly softer than those of ATLAS and CMS, and the presence of unique detectors, such as RICH, which is able to provide a measurement of the mass of long lived charged particles. Among others, LHCb has searched for displaced particles decaying to jets [4] or semi-leptonically [5] as well as long-lived heavy charged particles [6]. Although no evidence for new particles has been found, these results are useful to constraint the parameter space of several NP models. - Standard Model physics The SM is currently our best approach to explain the dynamics and behavior of particles at the subatomic level. The LHCb detector allows performing several measurements to test the precision of the SM, in some cases to an unprecedented level at a hadron collider. In this regard, the LHCb measurements are very useful to constrain the internal structure of the proton measuring the Z production in the forward region [7] or to probe hard QCD in a unique environment, providing the first evidence for certain processes, such as W+cc [8]. Furthermore, LHCb is expected to make relevant contributions to Higgs physics in the mid-term. On this subject, a first search for the decays H→bb or cc, with the Higgs produced in association with a W or Z boson has already been performed [9]. - Physics with heavy ions LHCb was not initially conceived for heavy ion physics. However, following the excellent performance of the detector and the increasing interest in this area at LHCb, data has been recorded in different configurations, including Pb-Pb, p-Pb and Pb-p collisions. Furthermore, LHCb can be turned into a fixed target experiment by injecting noble gases in the collision region. These special configurations can be very useful from a physics point of view. A remarkable example is that of the measurement of the anti-production in p-He collisions [10]. The production ratio between protons and anti-protons has been measured by several astroparticle experiments since it is a sensitive probe to dark matter in the Universe. Given that the dominant uncertainty to better understand this ratio comes from the anti-proton production, the measurement of the anti-proton production cross section in p-He collisions is crucial and becomes an excellent example of the contributions that LHCb can make in this regard. - References [1] LHCb Collaboration, Observation of the rare Bs→μμ decay from the combined analysis of CMS and LHCb data; Nature 522, 68-72 (2015). [2] LHCb Collaboration, Measurement of the CP-violating phase ϕs in the decay Bs→J/ψϕ; PRL 108, 101803 (2012). [3] LHCb Collaboration, Observation of J/ψp resonances consistent with pentaquark states in Λb→J/ψKp decays; PRL 115, 072001 (2015). [4] LHCb Collaboration, Search for long-lived particles decaying to jet pairs with the LHCb Run 1 data (to appear as LHCb-PAPER-2016-065). [5] LHCb Collaboration, Search for massive long-lived particles decaying semileptonically in the LHCb detector; EPJC (2017) 77: 224 [6] LHCb Collaboration, Search for long-lived heavy charged particles using a ring imaging Cherenkov technique at LHCb; EPJC 75 (2015) 595. [7] LHCb Collaboration, Measurement of the forward Z boson production cross-section in pp collisions at √s = 13 TeV; JHEP 09 (2016) 136. [8] LHCb Collaboration, Measurement of forward tt, W+bb and W+cc production in pp collisions at √s = 8 TeV; PLB767 (2017) 110. [9] LHCb Collaboration, Search for H→bb or cc in association with a W or Z boson in the forward region of pp collisions; LHCb-CONF-2016-006 [10] LHCb Collaboration, Measurement of antiproton production in pHe collisions at √sNN = 110 GeV (to appear as LHCb-CONF-2017-002).
        Speaker: Mr. Xabier Cid Vidal (USC - IGFAE)
        Slides
      • 17:15
        Estudio del vértice Wtb en la producción y desintegración del quark top producido en el canal t en colisiones pp a 8TeV con el detector ATLAS 30m
        En el LHC, los quarks top se producen principalmente en pares top-antitop. Sin embargo, también se pueden producir quarks top únicos mediante procesos electrodébiles con la presencia del vértice Wtb. Debido a la estructura V-A de éste vértice, los quarks top producidos están muy polarizados. Por tanto, la presencia de nueva física que afectara al vértice Wtb afectaría también a la polarización del quark top y del bosón W resultante de su desintegración. El análisis presentado muestra el estudio de la estructura del vértice Wtb realizado mediante la medida de observables de polarización en eventos de quarks top únicos en el canal t, producidos en colisiones protón-protón a una energía en centro de masas de 8 TeV. Los datos corresponden a una luminosidad integrada de 20.2 fb-1, registrados con el detector ATLAS en el LHC.
        Speaker: Ms. Laura Barranco Navarro (ific)
        Slides
      • 17:45
        D3-D5 theories with unquenched flavors 30m
        We construct the string duals of the defect theories generated when Nf flavor D5-branes intersect Nc color D3-branes along a 2+1 dimensional subspace. We work in the Veneziano limit in which Nc and Nf are large and Nf =Nc is fixed. By smearing the D5-branes, we find supergravity solutions that take into account the backreaction of the flavor branes and preserve two supercharges. When the flavors are massless the resulting metric displays an anisotropic Lifshitz-like scale invariance. The case of massive quarks is also considered
        Speaker: Mr. J. Manuel Penín (University of Santiago de Compostela)
    • 15:15 19:20
      Plasma Physics I Aula Química Analítica (Facultad de Química (USC))

      Aula Química Analítica

      Facultad de Química (USC)

      • 15:15
        Welcome and presentation of the simposium; Chairperson: Prof. Francisco L. Tabarés 15m
      • 15:30
        ITER’s Design Physics Basis and Research Plan 50m
        The ITER project’s mission is to demonstrate the scientific and technological feasibility of fusion power for peaceful purposes and the facility is now under construction at Saint Paul-lez-Durance (France). The ITER reactor is based on the tokamak concept of plasma magnetic confinement, in which the fusion (deuterium-tritium) fuel is contained in a toroidal vessel. The ITER tokamak is designed to generate 500 MW of fusion power for periods of 300 to 500 seconds with a fusion power multiplication factor, Q, of at least 10 (Q ≥10). ITER will also aim at demonstrating long fusion power production pulses, of at least 1000 seconds, with a fusion power multiplication factor of 5 and, ultimately, of approximately 1 hour duration (only limited by hardware design limits) when fully non-inductive operation is demonstrated. The paper will cover the main aspects of the ITER reactor design, construction and planned operation: a) The main features of the ITER tokamak reactor design. b) The basic physics design principles of the ITER tokamak and of the key ancillary systems required for the operational scenarios considered to achieve the project’s mission. c) The research plan from non-nuclear hydrogen and helium plasmas to nuclear operation with deuterium-tritium plasmas leading to the demonstration of high Q fusion power. This will include an in depth description of the key physics processes that need to be understood in detail and controlled for the achievements of ITER’s high Q goals including: 1) The reduction of the overall turbulent transport level to achieve the required energy confinement. 2) The control and mitigation of plasma magnetohydrodynamic instabilities, chiefly disruptions, edge localized modes and neoclassical tearing modes, etc. 3) The control of the power fluxes to the components that protect the vacuum vessel wall from the plasma and the minimization of the contamination of the plasma by impurities produced in plasma-wall interactions. 4) Heating and fuelling of the plasma by external means to ensure that the thermonuclear plasma conditions required to achieve high fusion gain are established in the tokamak. The paper will address the present understanding of these above, their implications for ITER operation and expected fusion performance, and the status of R&D on these issues for ITER, with emphasis on their unresolved aspects and possible ways to address them by new experiments, theoretical developments and simulations.
        Speaker: Dr. Alberto Loarte (ITER Organization)
      • 16:20
        New insights into plasma physics in the stellarator TJ-II using pellet injection 20m
        Pellet injection systems have recently been installed on the stellarator TJ-II. These systems allow controlled amounts of plasma fuel (hydrogen) or impurity elements (TESPEL) to be injected into the hot magnetically confined plasmas created in this heliac device. This has opened the way to new research areas in this machine. For example, core fuelling efficiency, pellet ablation and fuel deposition, as well as plasma reaction and reorganization to an instantaneous cooling and the subsequent increase in electron density. In addition, the TJ-II system also allows benchmarking of simulation codes for pellet ablation and deposition which will provide valuable input for future experiments on the recently commissioned large stellarator, the W7-X located in Greifswald, Germany.
        Speaker: Dr. Kieran Joseph McCarthy (Ciemat)
      • 16:40
        Calculation of electron capture cross sections in ion collisions with molecules formed in plasma-wall interaction 20m
        We present calculations of total cross sections for electron capture between protons and BeH molecules at collision energies between 25 eV and 10 keV. We have employed the semiclassical approximation and the sudden approximation for rotation and vibration. Our results show that the electron capture cross section is sizeable and may be relevant in plasma modelling.
        Speaker: Prof. Luis Méndez (Departamento de Química Universidad Autónoma de Madrid)
        Slides
      • 17:00
        Coffee break 20m
      • 17:20
        Testing Liquid Metal/Capillary Porous System Concepts as alternative solution for the Divertor target design of a Fusion Reactor in TJ-II 20m
        The use of liquid metals as plasma facing components (PFCs) in a future fusion reactor has been proposed as an alternative to solid metals, such as tungsten and molybdenum among others [1]. They offer unique properties as Plasma Facing Materials for a Fusion Reactor; they are basically free from permanent damage by neutron and plasma irradiation and can be re-circulated and regenerated for lifetime and particle and heat exhaust issues. The expected advantages for the power exhaust issues, mainly arising at the divertor target at power densities of 10– 20 MWm−2, relay on the self-healing properties of liquid surfaces as well as the ability to in situ replacement of the surfaces exposed to the plasma by the effect of capillary forces (CPS design, [2]). Among the possible liquid metals (LM) presently considered as candidates for the development of an alternative solution to the Power Exhaust Handling in a future Fusion Reactor (Li, Sn, Ga), tin lithium alloys offer unique properties in terms of evaporation, fuel retention and plasma compatibility. This is the reason why this particular LM was chosen as main candidate in the US APEX project [3]. Very recently, LiSn (20-30:80-70at.%) alloys have been exposed to ISTTOK and TJ-II and very promising results on D retention and surface segregation of Li were obtained [4,5]. Motivated by these results a full campaign of comparative Li/ LiSn/Sn testing in TJ-II plasmas has been initiated. Liquid metal wetted CPS heatable electrodes have been manufactured in the Plasma Wall Interaction laboratory at CIEMAT and later exposed to TJII plasmas at different temperatures. For both solid and liquid states a negligible perturbation of the plasma has been recorded in the Li and LiSn cases, even when stellarator plasmas are particularly sensitive to high Z elements due to the tendency to central impurity accumulation. The surface temperature of the liquid metal/CPS electrodes (made of a Tungsten mesh impregnated in SnLi, Sn or Li) has been measured during the plasma pulse with ms resolution by pyrometry and the thermal balance during heating and cooling has been used to obtain the thermal parameters of the LM/CPS arrangements as well as to calculate the thickness of the film interacting with the plasma. Temperatures as high as 1100K during TJ-II plasma exposure were observed for the LiSn case and hints of sputtering-enhanced evaporation were deduced from the temperature dependence of the lithium fluxes entering the plasma. Furthermore, laboratory experiments showing a much lower hydrogen retention of SnLi compared to Li (as expected) and a secondary emission coefficient (SEE) closer to pure Li have been undertaken in order to further study the relevant properties of tin lithium alloys for their possible use as PFC in a future reactor. In this presentation a full account of the results obtained and their implications for the use of LM/CPS concepts in a future Fusion Reactor will be addressed. This research was partially financed by the Spanish “Ministry of Economy and Competitivity” under project ENE2014-58918-R. [1] R. Nygren and F.L.Tabarés , Nucl. Mater. Ener. 9 (2016) 6-21 [2] S.V.Mirnov et al. Nucl. Fusion 51 (2011) 073044 [3] M.A. Abdou et al,Fusion Eng. Des. 54 (2001) 181–247 [4] J. Loureiro et al. Fus. Eng. Des. (2017) http://dx.doi.org/10.1016/j.fusengdes.2016.12.031 [5] F. L. Tabares et al., Nuclear Materials and Energy 000 (2016) 1-6. http://dx.doi.org/10.1016/j.nme.2016.11.026
        Speaker: Dr. eider oyarzabal (Fusion National Laboratory CIEMAT, Av Complutense 40, Madrid 28040, Spain)
      • 17:40
        TEMPERATURE DEPENDENCE OF LIQUID LITHIUM FILM FORMATION AND DEUTERIUM RETENTION ON HOT W SAMPLES BY LIDS AND TDS. IMPLICATIONS FOR FUTURE FUSION REACTORS 20m
        The development of magnetic fusion reactors needs to solve the challenging power/particle exhaust issues to assure a long pulsed/steady state operation avoiding unacceptable damage to the Plasma Facing Materials (PFM’s) that would limit their useful life and the feasibility of such power plants. Although nowadays the use solid tungsten (W) components constitute the main investigated option for these requirements, there are serious concerns over their limitations, especially for the case of unmitigated heat flux and transients handling on the divertor. Liquid metal (LM) divertor concepts explore an alternative solution as their surfaces are, in principle, renewable and unscathed to permanent degradation and disintegration. Moreover, evaporation and high edge non coronal radiation (vapor shielding) can help in this task, reducing the power loads to the surrounding walls. Among LM’s, lithium (Li) is the most promising and studied material. Its employment has shown important advantages in terms of improved H-mode plasma confinement and heat handling capabilities. In such scenario, a possible combination of tungsten at the first wall and liquid Li at the divertor could be an acceptable solution, but several issues related with this material compatibility must be investigated. The co-deposition of Li and hydrogen isotopes on W components could increase the associated tritium retention and might represent an important hazard in terms of radioactive safety. In this work, the co-deposition of Li and deuterium (D) on tungsten at different surface temperature (200ºC-400ºC) has been studied by exposing W samples to Li evaporation under several D2 gaseous environments. Deuterium retention in the W-Li films has been quantified by using Laser Induced Desorption Spectroscopy (LIDS). Additional techniques as Thermal Desorption Spectroscopy (TDS), Secondary Ion Mass Spectrometry (SIMS), profilemetry and Flame Atomic Emission Spectroscopy (FAES) were implemented to corroborate the retention results and for the qualitative and quantitative characterization of the W-Li films. The results show a negligible (below the limit of detection) D uptake by the W-Li layer at Tsurface=225ºC, when it is exposed to simultaneous Li evaporation and low pressure (0.67 Pa) D2 gas exposition. Pre-lithiated samples were also exposed to higher D2 pressures (133.3 Pa) at different superficial temperatures (200ºC-400ºC). A non-linear drastic reduction in the D retention was found for increasing temperatures on the W-Li films that determined D/Li atomic ratios lower that 10-4 at 400ºC. The implication of these results in the potential implementation of this PFM’s solution is considered. Based on the experimental results, an extrapolation of the D co-deposition on W-Li first wall areas in DEMO reactor designs is performed, showing that the associated fuel retention in such hot first wall may be compatible with the tritium inventory limitations.
        Speaker: Mr. Alfonso de Castro Calles (Fusion National Laboratory-CIEMAT)
      • 18:00
        Perturbaciones rotacionales de velocidad en flujos de Richtmyer-Meshkov 20m
        Las ondas de choque corrugadas generan perturbaciones de velocidad, entropía, vorticidad y presión (en forma de ondas acústicas). Su estudio es importante en conexión con la inestabilidad de Richtmyer-Meshkov, con aplicaciones en Fusión por Confinamiento Inercial y Materia con alta densidad de energía en general, sea porque los flujos asociados empeoran las condiciones de simetría en la irradiación de blancos, o porque se los usa como herramientas diagnósticas. Se presenta un modelo que permite calcular los campos de velocidad generados por ondas de choque corrugadas en 2D en función del espacio y del tiempo. Se estudia el campo de vorticidad asociado y la energía cinética contenida en los vórtices más intensos, para diversas condiciones de contorno en la superficie que genera el choque.
        Speaker: Prof. Juan Gustavo Wouchuk Schmidt (Universidad de Castilla La Mancha)
      • 18:20
        Estudio analítico de la Inestabilidad de Richtmyer-Meshkov para saltos arbitrarios de densidad en la superficie de contacto 20m
        Cuando una onda de choque plana incide sobre una superficie que separa dos fluidos, un choque siempre se transmite hacia delante y otro choque o una rarefacción se refleja dependiendo de la diferencia de densidad inicial entre ambos fluidos y de sus compresibilidades. Por otra parte, si la interfase está ondulada, se generarán perturbaciones hidrodinámicas en el interior de los dos fluidos. Como resultado, sobre la superficie de contacto aparecen fluctuaciones de velocidad normales y tangencias, las cuales provocan que su corrugación aumente indefinidamente. Esta situación se denomina Inestabilidad de Richtmyer-Meshkov. Dicho fenómeno, es determinante en las etapas iniciales de compresión de las cápsulas de combustible utilizadas en la Fusión por Confinamiento Inercial (ICF), en las investigaciones con tubos de choque, en la interacción de ondas de choque con flujos turbulentos y en el estudio de materia en estados de alta densidad de energía (HEDP). En nuestro trabajo hemos estudiado la fase lineal del problema y hemos resuelto analíticamente la evolución temporal de los campos perturbados en el espacio comprendido entre ambos frentes, partiendo de principios básicos y teniendo en cuenta la compresibilidad de forma rigurosa. Especial atención merece la evolución de la corrugación en la superficie de contacto, la cual hemos calculado desde el instante en el que el choque incidente desaparece (), hasta que alcanza su etapa asintótica lineal. Hemos comparado el modelo teórico con simulaciones y experimentos realizados en una amplia variedad de condiciones iniciales y el acuerdo, en los casos donde se puede aplicar la teoría lineal, es excelente. Debido a la complejidad del modelo matemático y con la finalidad de facilitar un cálculo rápido y sencillo, presentamos fórmulas aproximadas para el cálculo de las velocidades asintóticas para intensidad de choque incidente arbitraria.
        Speaker: Mr. Francisco Cobos-Campos (E.T.S.I. Industriales, Instituto de Investigaciones Energeticas, and CYTEMA, Universidad de Castilla-La Mancha, 13071 Ciudad Real, Spain)
      • 18:40
        Estudio de propiedades microscópicas de plasmas de experimentos de astrofísica de laboratorio 20m
        La Astrofísica de Laboratorio (AL) es un tópico de investigación dentro del campo de la física de alta densidad de energía que ha venido ganando importancia en las dos últimas décadas, siendo en la actualidad un área que atrae mucha atención. El campo de la AL abarca el estudio teórico y experimental de la física que subyace bajo ciertos fenómenos físicos observados en el cosmos, en un régimen susceptible de presentarse en un laboratorio, evitando los inconvenientes que el análisis observacional suele presentar, tales como la distancia entre el observador y el fenómeno de estudio, las limitaciones tecnológicas, la imposibilidad de acceder al fenómeno en varias ocasiones, de repetirlo, o la imposibilidad de controlar las condiciones bajo las cuales se producen dichos fenómenos. En este sentido, la AL, que permite la cercanía al fenómeno y la capacidad de controlarlo y repetirlo, ha abierto un nuevo camino que usan los astrofísicos, y que une a físicos experimentales y teóricos en la investigación del Universo, ofreciendo además nuevos puntos de vista en los procesos de interpretación de los datos observacionales y de las teorías actuales sostenidas por la Astrofísica Moderna. Además, los experimentos realizados en el contexto de la AL proporcionan datos para la verificación y la validación de diversos aspectos de los códigos numéricos tales como la física atómica, la hidrodinámica, las ecuaciones de estado y la transferencia radiativa, códigos que se emplean en diversos campos de la física de alta densidad de energía. Dos han sido los desarrollos que han contribuido al diseño exitoso de experimentos de AL. El primero es que se ha comprobado que la hidrodinámica puede ser escalada correctamente entre los escenarios astrofísicos y el laboratorio. Este hecho fue presentado por primera vez en el trabajo pionero de Ryutov et al. para un escenario astrofísico concreto (remanentes de supernova). Desde entonces, las condiciones que han de verificarse para un correcto escalado de un fenómeno astrofísico en laboratorio han sido extendidas a escenarios más complejos, incluyendo campos magnéticos o campos de radiación intensos. El segundo desarrollo ha sido el empleo de láseres intensos y dispositivos de potencia pulsada, pensados inicialmente para otros campos de la alta densidad de energía como la fusión por confinamiento inercial, para conseguir las condiciones necesarias para los experimentos de AL, ya que permiten colocar a la materia en estados extremos de temperatura, densidad y velocidad. Como se comentó anteriormente, los datos que proporcionan los experimento de AL son muy valiosos para verificar y validar los modelos teóricos y computacionales habitualmente empleados en la física de alta densidad de energía. En la bibliografía es común encontrar simulaciones hidrodinámicas (y, por tanto, macroscópicas) de los experimentos de AL, detectándose un vacío en el estudio, análisis y determinación de las propiedades microscópicas en el correcto estado termodinámico de los mismos (tales como ionizaciones medias, distribuciones iónicas, la cinética de poblaciones o las propiedades radiativas) de los plasmas generados en dichos experimentos. Sin embargo, este estudio microscópico es fundamental ya que muchas de estas propiedades microscópicas son necesarias para las simulaciones hidrodinámicas (opacidades e ionizaciones medias y pérdidas de potencia radiativas, entre otras, que muy comúnmente son calculadas en esas simulaciones con modelos atómicos sencillos o con modelos de cinética atómica simplificados basados en suponer al plasma en equilibrio Corona o equilibrio termodinámico local, ETL, aunque no se verifiquen las condiciones de los mismos), para la transferencia radiativa y para la diagnosis espectroscópica de las condiciones del plasma. Además, estos estudios microscópicos permiten conocer también la importancia de los efectos de reabsorción de la radiación (plasma grueso o delgado), de la estacionariedad o no del plasma, de los campos de radiación externos (plasmas fotoionizados), del régimen termodinámico del plasma (ETL o NETL) o de la presencia de diferentes elementos en el plasma (plasma multicomponente). Este trabajo se enmarca dentro de ese contexto. Debido a nuestra participación como grupo teórico en varios experimentos de AL en el último lustro, hemos realizado análisis microscópicos de los plasmas que se generan en los mismos, con el fin de ilustrar los efectos anteriormente comentados en dichos experimentos y así servir de ayuda en las simulaciones hidrodinámicas posteriores, además de proporcionar información acerca de lo que ocurre microscópicamente en dichos experimentos. Con el fin de mostrar los estudios realizados, hemos seleccionado dos experimentos en particular. En el primero, se analizaron las ondas de choque radiativas generadas en laboratorio a través de la absorción de un láser intenso por un cluster de átomos de xenón o kriptón, las cuales emulaban las que se observan en los remanentes de supernova. En el segundo, se estudió las propiedades microscópicas de un jet de aluminio que se generaba en un dispositivo de potencia pulsada y de las ondas de choque que se creaban en la propagación de dicho jet en argón. El objetivo de este experimento era la reproducción en laboratorio de los jets que se generan en la formación de estrellas jóvenes y la interacción de los mismos con el medio interestelar. En ambos experimentos analizamos, también, de forma teórica la posibilidad de la aparición de inestabilidades térmicas por enfriamiento radiativo del plasma chocado que se encuentra justo detrás del frente de las ondas de choque radiativas generadas en esos experimentos. El estudio de dichas inestabilidades se hace comúnmente a través de la parametrización del coeficiente de enfriamiento. En nuestro estudio, dicha parametrización se realiza en función de la densidad y de la temperatura usando el código PARPRA y no solo de la densidad, como es común encontrarla en la bibliografía, ya que el plasma en los experimentos de AL se encuentra, en general, en NETL y la contribución más relevante a la emisión de radiación es la de transición de línea, a diferencia de los fenómenos astrofísicos que se emulan. Para nuestro estudio teórico empleamos nuestros códigos para el cálculo de la cinética de poblaciones, MIXKIP [7], y de propiedades radiativas, RAPCAL [8]. Estos códigos permiten el cálculo de las poblaciones de nivel de los plasmas y las propiedades radiativas para plasmas mono y multicomponentes, en estado estacionario o no, delgados o gruesos, de número atómico alto, medio y bajo, en ETL y NETL e incluyendo campos de radiación externos.
        Speaker: Dr. Guadalupe Espinosa (Universidad de Las Palmas de Gran Canaria)
      • 19:00
        Dinámica de la expansión de una onda de choque producida en un sistema de alambre explosivo 20m
        Dentro de los numerosos mecanismos para crear plasmas en condiciones controladas, destaca por su aparente sencillez el alambre explosivo. Consiste en una red RLC de alto voltaje que descarga toda la energía almacenada a través de un alambre metálico o conductor de manera que la corriente que circula por él, típicamente del orden de 10 kA,crea un plasma metálico en expansión, con una onda de choque previa. En este trabajo se presentan resultados experimentales sobre la dinámica de esta onda de choque.
        Speaker: Mr. Gonzalo Rodríguez Prieto (ETSII - UCLM)
        Slides
    • 15:15 19:05
      Quantum Technologies: joint symposium of the Quantum Information and Quantum and Non-linear Optics specialised groups Aula Química General (Facultad Química (USC))

      Aula Química General

      Facultad Química (USC)

      • 15:15
        Conexión de iones en distintas trampas mediante corrientes inducidas 20m
        La conexión de dos iones confinados en dos trampas electromagnéticas (Paul o Penning) diferentes mediante las corrientes que estos inducen en un electrodo común constituye un gran reto tecnológico que no se ha conseguido hasta la fecha. La conexión o acoplamiento daría lugar a aplicaciones de gran interés en el ámbito de la física fundamental, como son la detección de corrientes de radiofrecuencia con sensibilidad sin precedentes o el intercambio de información cuántica entre dos iones [1,2]. El proyecto TRAPSENSOR [3,4] se inició en la Universidad de Granada con el objetivo de construir un sistema de dos trampas Penning de 7-Tesla, conectadas mediante un hilo conductor. En una de las trampas se almacenará un ion de 40Ca+ enfriado mediante láser, mientras que en la otra se confinará un ion de cualquier especie cuya masa se quiere medir con precisión. La conexión entre los dos iones, a través de las corrientes inducidas y que se transmiten por el hilo conductor, permitiría tanto enfriar simpatéticamente el ion desconocido, como medir su frecuencia de oscilación utilizando campos externos variables [5], y por tanto su relación carga-masa. El desarrollo de este proyecto está generando una tecnología extrapolable a otras aplicaciones cuánticas. En esta contribución, presentamos el laboratorio de Trampas de Iones y Láseres de la Universidad de Granada [6] en el que se está desarrollando el proyecto TRAPSENSOR. Discutimos los distintos enfoques que estamos utilizando para alcanzar con éxito el objetivo del proyecto, lo que incluye el enfriamiento por láser de iones en trampas de Paul y Penning, la detección de su fluorescencia, la electrónica asociada a la conexión de dos trampas a temperatura criogénica y la construcción de un sistema de micro-trampas Penning que permita el acoplamiento de manera efectiva. También expondremos los resultados más relevantes obtenidos hasta la fecha. En particular, hemos realizado experimentos para estimar la sensibilidad de un único ion de 40Ca+ enfriado hasta el límite Doppler en una trampa de radiofrecuencia a corrientes aplicadas a uno de los electrodos, mientras que hemos conseguido el atrapamiento estable en la trampa de Penning de 7-Tesla a temperatura ambiente. Figura 1. Fotografía del sistema doble de micro-trampas Penning construido. Agradecimientos Este proyecto está financiado por el Consejo Europeo de Investigación (ERC StG 278648-TRAPSENSOR) junto con los proyectos MINECO/FEDER FPA2012-32076, FPA2015-67694-P, UNGR10-1E-501, FIS2015-69983-P y UNGR13-1E-1830, y Junta de Andalucía/FEDER IE_57131. Referencias [1] D.J. Heinzen, D.J Wineland, Phys. Rev. A 42, (1990) 2977. [2] N. Daniilidis, T. Lee, R. Clark, S. Narayanan, and H. Häffner, J. Phys. B 42, (2009) 144012 [3] D. Rodríguez, Appl. Phys. B 107, (2012) 1031 [4] J.M. Cornejo, M.J. Gutiérrez, E. Ruiz, A. Bautista-Salvador, C. Ospelkaus, S. Stahl, D. Rodríguez, Int. J. Mass Spectrom. 410C, (2016) 22 [5] L.S. Brown and G. Gabrielse, Rev. Mod. Phys. 58 (1986) 233 [6] http://trapsensor.ugr.es
        Speaker: Dr. Raúl Rica Alarcón (Universidad de Granada)
      • 15:35
        Fast and Robust Phase Gates with Trapped-Ion Hyperfine Qubits 20m
        I will present a proposal for generating fast and robust quantum phase gates between two microwave-driven hyperfine ions, making use of a pulsed dynamical decoupling protocol. The scheme consists of a series of pi-pulses that are applied individually to each ion, whose internal level act as a qubit. Unlike previous proposals, this gate uses both axial vibrational modes as the quantum bus between both qubits. In this way, we are able to achieve a higher gate speed. In addition, I will argue that the proposed gate is robust against most harmful noise sources, related with fluctuations of the Rabi frequency or the magnetic field. Our numerical simulations show that with state-of-the-art ion trap technology, entangling gates with fidelities above 99.9% can be produced in tens of microseconds.
        Speaker: Mr. Iñigo Arrazola (University of the Basque Country)
      • 15:55
        Quantum Walking the number of quanta probability distribution 20m
        We present schemes based on the alternation between Jaynes-Cummings (JC) and anti-JC Hamiltonians for implementing quantum walks along the number of quanta " line", i.e., which provides new means for quantum state manipulation
        Speaker: Prof. Eugenio Roldán Serrano (Universitat de Valencia)
      • 16:15
        Quantum-enhanced Landauer erasure and storage of a molecular magnetic bit 20m
        The erasure of a bit of information encoded in any physical system is an irreversible operation bound to dissipate an amount of energy Q = kBT ln 2 [1]. As a result, work W ≥ Q has to be applied to the physical system to restore the erased information content [2-4]. This limit, called Landauer limit, sets a minimal energy dissipation inherent to any classical computation. In the pursuit of the fastest and most efficient means of computation, the ultimate challenge is to produce a memory device executing an operation as close to this limit in the shortest time possible. Here, we use a single crystal of Fe8 molecular nanomagnets as a spin-memory device. Each molecular cluster carries a net spin S = 10 and possesses a strong uniaxial magnetic anisotropy. The ground state corresponds to maximum spin projections Sz = +10 and -10 along the anisotropy axis, common to all molecules, which define the ‘0’ and ‘1’ bit states (Fig. 1(a)). These states are separated by an energy barrier U/kB ≈ 24 K, which hinders the spin flip and gives rise to magnetic hysteresis, thus magnetic memory, below approximately 1.2 K [5,6]. In our experiments, the Landauer cycle is performed, at T = 1 K, via the application of a sequence of magnetic fields aligned along different orientations with respect to the magnetic anisotropy axis (Fig. 1(b)). The erasure is induced by a transverse magnetic field Hy, which reduces the height of the magnetic energy barrier and promotes tunneling between quasi-degenerate spin projections, thus exploiting a form of quantum annealing [7,8]. The bits are then recorded by applying a magnetic field Hz along the anisotropy axis, strong enough to polarize their magnetic moments. The cycle is then completed by reducing first Hy and then Hz back to zero. The magnetic susceptibility along z and y has been measured (Fig. 1(c)) and then integrated to obtain the net magnetic work required to perform the erasure and recording cycle. It agrees, within experimental uncertainties, with the Landauer limit. The ac susceptibility provides also information about the magnetization dynamics and, in particular, enables us to estimate the time needed to record each bit. This time turns out to be shorter than 0.1 micro-seconds thanks to the very fast quantum spin dynamics induced by the transverse magnetic field. The performance of our device in terms of energy-time cost is then orders of magnitude better than that of any existing memory devices to date. Acknowledgments The research reported here was supported by the Spanish MINECO (grant MAT2015-68204-R), the Dutch Organization for Fundamental research (NWO/FOM), the Gobierno de Aragón (grant E98-MOLCHIP) and the European Union (advanced ERC grant Mols@Mols and COST 15128 Molecular Spintronics project). References [1] R. Landauer, IBM Journal of Research and Development 5 (1961) 183. [2] C. H. Bennett, International Journal of Theoretical Physics 21 (1982) 905. [3] C. H. Bennett, IBM Journal of Research and Development 32 (1988) 16. [4] H. Leff and A. Rex, Maxwell's demon: Information, entropy, computing, Hilger and Princeton Univ. Press, Europe/USA (1990). [5] W. Wernsdorfer, R. Sessoli, A. Caneschi, D. Gatteschi and A. Cornia, EPL 50 (2000) 552. [6] E. Burzurí, F. Luis, O. Montero, B. Barbara, R. Ballou, and S. Maegawa, Phys. Rev. Lett. 111 (2013) 057201. [7] J. Brooke, D. Bitko, T. F. Rosenbaum and G. Aeppli, Science 284 (1999) 779. [8] E. Burzurí, F. Luis, B. Barbara, R. Ballou, E. Ressouche, O. Montero, J. Campo, and S. Maegawa Phys. Rev. Lett. 107 (2011) 097203.
        Speaker: Dr. Fernando LUIS (Instituto de Ciencia de Materiales de Aragón, CSIC)
      • 16:35
        Characterising multi-photon quantum interference with decoy-state techniques 20m
        Correct characterization of general linear optical networks is becoming a promising task due to the continuous development in some fields as quantum computation and quantum communications, in which quantum optics is typically involved. Specifically, it is of great importance in several applications to know the photon number statistics at the outputs of the linear network as a function of the input photon number to check its quality. Although in recent years there have been some advances in multi-photon sources and photon number resolution a simple plug-and-play method for characterising general linear optics networks with enough accuracy is still missing. We propose a simple and practical method to estimate these photon number statistics that can be implemented with laser sources that generate quantum signals which are diagonal in the Fock basis in combination with threshold single-photon detectors.
        Speaker: Mr. Álvaro Navarrete Rodríguez (Universidad de Vigo)
      • 16:55
        Coffee break 30m
      • 17:25
        Causality in waveguide QED 20m
        Causality is one of the most fundamental principles in physics and it has strong implications. For instance, in QFT, the scattering matrix, the mathematical object connecting input and output free states, must follow the so-called cluster-decomposition principle, which says that the scattering amplitude factorizes as a product of single-particle amplitudes for causally disconnected input states. In this work, we find that the cluster-decomposition principle also occurs in a non-causal system: the nonrelativistic scenario of waveguide QED, where a one-dimensional photonic field interacts with some scatterers. We first show a Lieb-Robinson-like bond holds for the free theory, so the system is approximately causal if there are not scatterers. We then show that the ground state of the full model is equivalent to the vacuum far away from the scattering region, so we can properly define free input and output states. We then show the Lieb-Robinson-like bond also holds for the full system. Lastly, considering that there are more stable states apart from the ground state, we show that the scattering amplitude for a bunch of causally disconnected incident photons is composed by a product of one-photon amplitudes, with a sum over all the stable states, so the cluster-decomposition principle holds. We find the structure for the S-matrix in position space compatible with this scattering amplitude. We finally illustrate our results with two examples: (i) a two-level system ultrastrongly coupled to a dispersive medium and (ii) a general scatterer coupled to a waveguide with linear dispersion relation. In the first example, we show the cluster properties hold. In the second one, we find the structure for the S-matrix in momentum space and compute how the photon-photon correlations generated by this S-matrix decay with the distance between the incident photons.
        Speaker: Mr. Eduardo Sánchez-Burillo (Instituto de Ciencia de Materiales de Aragón (CSIC-Unizar))
        Paper
      • 17:45
        Single-atom edgelike states via quantum interference 20m
        Recent theoretical and experimental studies have shown that it is possible to simulate artificial magnetic fields with ultracold atoms in optical lattices [1]. In particular, the possibility to implement chiral, topologically protected edge states analogous to those found in the context of quantum Hall physics has been demonstrated both for fermionic and bosonic atoms [2,3]. In this work, we propose an alternative strategy to implement robust edgelike states (ELS) in optical ribbons, which we model by regarding each of the sites as a two-dimensional harmonic trap of equal frequency, with a single atom carrying l = 0 or l = 1 orbital angular momentum (OAM) units. First, we consider a system of three in-line sites governed by tunneling dynamics, which can be described by a few-state model. We show that in this system quantum interference effects give rise to spatial dark states (SDS), i.e., states in which one site remains unpopulated along the time evolution. Then, we show that by using the SDS as basic building blocks, global ELS can be created in arbitrarily large ribbons. These ELS are very robust against defects in the ribbon and perturbations in the phase differences between the local eigenstates of the sites required to have quantum interference [3]. For the l = 0 case, the tunneling amplitudes between sites are always real and interference effects are solely induced by phase differences between the populated sites. This fact allows one to create ELS within this manifold and switch between them in a very straightforward manner by applying laser pulses, as shown in the left panel of figure 1, and also opening the possibility to implement similar ELS in more complex geometries. For the l = 1 case, the few-state description is richer because the tunneling amplitudes depend both on the spatial localization and the winding number of the local states, and they may become complex depending on the relative position of the sites [4]. The ELS implemented in this manifold can display global chirality, as shown in the right panel of figure 1. Another interesting possibility that this manifold offers is to simulate an extra dimension by regarding the winding number as a synthetic dimension.
        Speaker: Mr. Gerard Pelegrí (Universitat Autònoma de Barcelona)
      • 18:05
        Measurement-Device-Independent Quantum Key Distribution with Information Leakage 20m
        Measurement-device-independent quantum key distribution (MDI-QKD) is proposed to remove all the detection side-channels in quantum communication systems. In recent years, MDI-QKD has been proven to be secure with certain assumptions and become a significant step toward the practicality of QKD systems. However, the assumption that there is no information leakage from the security zones of the legitimate parties seems very difficult to be guaranteed in practice. In this work we relax this assumption by proposing a general formalism to prove the security of MDI-QKD in the presence of information leakage. Particularly, we analyze a specific Trojan-Horse attack on the intensity modulator and phase modulator and the secure key rates under different amounts of information leakage are calculated in several practical cases. Our work provides an essential reference for experimentalists to ensure the security when implementing MDI-QKD protocols in the presence of information leakage.
        Speaker: Mr. Weilong Wang (University of Vigo)
      • 18:25
        Nanoscale control of antenna-coupling strength g for bright single photon sources 20m
        Cavity QED is the art of enhancing light-matter interaction of photon emitters in cavities, with opportunities for sensing, quantum information and energy capture technologies. To boost emitter-cavity interaction, i.e. coupling strength 𝑔, ultrahigh quality cavities have been concocted yielding photon trapping times of µs to ms. However, such high-Q cavities give poor photon output, hindering applications. To preserve high photon output it is advantageous to strive for highly localised electric fields in radiatively lossy cavities. Nanophotonic antennas are ideal candidates combining low-Q factors with deeply localised mode volumes, allowing large 𝑔, provided the emitter is positioned exactly right inside the nanoscale mode volume. Here, with nanometre resolution, we map and tune the coupling strength between a dipole nanoantenna-cavity and a single molecule, obtaining a coupling rate of 2𝑔max = 412 GHz. Together with accelerated single photon output, this provides ideal conditions for fast and pure non-classical single photon emission with brightness exceeding 10E9 photons/sec. Clearly nanoantennas, acting as “bad” cavities, offer an optimal regime for strong coupling 𝑔, to deliver bright on-demand and ultrafast single photon nanosources for quantum technologies.
        Speaker: Prof. Niek F. van Hulst (ICFO - the Institute of Photonic Sciences)
      • 18:45
        Bichromatically driven Kerr-like cavities and vacuum squeezing generation. 20m
        Here we theoretically analyse the generation of strong vaccum squeezing in optomechanical, superconducting circuits and polariton cavities driven by a bichromatic field . This proposal has the following advantages over the usual proposals with mochromatic driving: the process is unrelated to bistability which is good for stability issues and the reduction of fluctuations takes place at a non-injected frequency, thus one obtains a squeezed vacuum state
        Speaker: Mr. Rafael Garcés Malonda (Departament d'Òptica, Universitat de València)
    • 19:30 20:30
      Plenary: outreach Aula Magna

      Aula Magna

      Santiago de Compostela, Facultade de Química

      Av. das Ciencias s/n, 15701 Santiago de Compostela, A Coruña, Spain
      • 19:30
        La teoría de la evolución y sus implicaciones: ¿una verdad incómoda? 1h
        La teoría de la evolución y sus implicaciones: ¿una verdad incómoda?
        Speaker: Prof. José Adolfo de Azcárraga Feliu (IFIC)
    • 09:00 13:40
      Plenary III Aula Magna

      Aula Magna

      Santiago de Compostela, Facultade de Química

      Av. das Ciencias s/n, 15701 Santiago de Compostela, A Coruña, Spain
      • 09:00
        New frontiers in superconductivity: Novel states and properties from topology and interfaces 50m
        More than 100 years have passed since the discovery of superconductivity. In the meantime this fascinating phenomenon has provided the basis for a wide range of important applications. Our fundamental understanding of superconductivity has been based on the theory of Bardeen, Cooper, and Schrieffer known as BCS which was published in 1957. Despite being a well-established field in quantum matter physics, superconductivity has been a continuous source of new discoveries during the past decade. The discoveries have been made possible by the progressive technical mastery of producing artificially structured quantum matter with tunable properties. Surfaces and interfaces play a key role in this context. On the theory side, "topology" emerged as a pervasive concept in characterizing and classifying novel states of quantum matter with fascinating and sometimes exotic properties. In the present talk I will review some recent developments and ideas which may give rise to opportunities for scientific discovery and potential applications.
        Speaker: Prof. Gertrud Zwicknagl
        Slides
      • 09:50
        Nanocosmos and Laboratory Astrophysics: from molecules to dust 50m
        Evolved stars are the factories of interstellar dust. This dust is injected into the interstellar medium and plays a key role in the evolution of astronomical objects from galaxies to the embryos of planets. However, the processes involved in dust formation and evolution are still a mystery. The increased angular resolution of the new generation of large telescopes, is providing for the first time a detailed view of the conditions in the dust formation zone of evolved stars, as shown by our first observations with ALMA (Cernicharo et al. 2013, Agúndez et al. 2017). The aim of the NANOCOSMOS project is to take advantage of these new observational capabilities to change our view on the origin and evolution of dust grains. We are combining astronomical observations, modelling, and top-level experiments to produce star dust analogues in the laboratory and identify the key species and steps that govern their formation. We have built two innovative setups: the Stardust chamber to simulate the physical conditions of the atmosphere of evolved stars, and the gas evolution chamber to identify novel molecules in the dust formation zone. We are also improving existing laboratory setups and combine different techniques to achieve original studies on individual dust grains, their processing to produce complex polycyclic aromatic hydrocarbons, the chemical evolution of grain precursors and how dust grains interact with abundant astronomical molecules. Our simulation chambers have been equipped with state-of-theart in situ and ex situ diagnostics. Our astrophysical models, improved by the interplay between observations and laboratory studies, provide powerful tools for the analysis of the wealth of data provided by the new generation of telescopes. The synergy between astronomers, vacuum and microwave engineers, molecular and plasma physicists, surface scientists, and theoreticians in NANOCOSMOS is the key to provide a cutting-edge view of cosmic dust.
        Speaker: Prof. José Cernicharo
      • 10:40
        Entrega premios Jóvenes Investigadores 10m

        Entrega de Diplomas y premios para los ganadores del Concurso Jóvenes investigadores

      • 10:50
        Cloaking magnetic information 20m
        During the last decade, in the field of multiferroic materials, several systems have shown the coexistence of electric and magnetic orders with coupling between them (so-called magnetoelectric coupling). In the particular class of composite multiferroics, where magnetoelectric coupling takes place owing to mechanical coupling (strain mediated) between a ferroelectric material and a ferromagnetic material, the sign of the net magnetization in the ferromagnet can not be selected uniquely by an electric field, whatever is its sign or magnitude. This is because piezoelectricity and magnetostriction (the mechanisms that trigger magnetoelectric coupling) are both even functions of electric field and strain, respectively. Without overcoming this fundamental issue, we will show by micro and macromagnetic characterization that magnetic memory effects present in the antiferromagnetic to ferromagnetic transition of FeRh can help to circumvent it. With this purpose, we have characterised a PMN-PT/FeRh structure. PMN-PT is a relaxor ferroelectric with record piezoelectric coefficient, and FeRh presents a large change in its lattice parameters while crossing the antiferromagnetic to ferromagnetic phase transition. Thus, one can tune the magnetic order by means of electric-field, by modifying the magnetic transition temperature on FeRh via strain coupling between the piezoelectric substrate and the magnetic layer. First, we will show that FeRh phase transition shows thermal memory effect. After the FeRh magnetization is oriented in the ferromagnetic phase by an external magnetic field and FeRh is brought to the antiferromagnetic phase by cooling it, if one measures the orientation of the magnetization again in the ferromagnetic phase, it partially recovers its initial state [1]. Secondly, we also show that by the application of low electric field, we can isothermally manipulate a large amount of magnetization. Magnetic imaging reveals that the electrically stimulated memory effect occurs thanks to the same mechanism that applies for the aforementioned thermal magnetic memory effect [2], as sketched in Figure 1. [1] J. Clarkson, …, I. Fina, et al., An invisible non-volatile solid-state memory, arXiv preprint arXiv:1604.03383 [2] I. Fina, et al., Electric-Field Adjustable Time-Dependent Magnetoelectric Response in Martensitic FeRh Alloy, ACS Applied Materials & Interfaces (2017). Online.
        Speaker: Dr. Ignasi Fina (Institut de Ciència de Materials de Barcelona (ICMAB-CSIC))
      • 11:10
        Coffee break and poster session 30m
      • 11:40
        Transversal Session II. Física para todos: Divulgación de la Física 2h
        Física para todos: Divulgación de la Física
        Speakers: Dr. Carmen Carreras (RSEF - UNED), Jorge Mira, Prof. Miguel-Angel Sanchis-Lozano (University of Valencia)
    • 13:40 15:00
      Lunch break 1h 20m Campus Vida USC

      Campus Vida USC

    • 15:00 19:45
      Nuclear Physics III Aula Física Química (Facultad de Química (USC))

      Aula Física Química

      Facultad de Química (USC)

      • 15:00
        El laboratorio TRAPSENSOR: Un laboratorio singular de la Universidad de Granada 25m
        A finales del 2011, empecé en la Universidad de Granada junto a dos estudiantes egresados de dicha universidad, un proyecto del Consejo Europeo de Investigación (ERC-StG-2011) con el título “High-Performance Mass Spectrometry Using a Quantum Sensor” en el que proponía una idea para implementar un método novedoso para la detección de la corriente que puede inducir en los electrodos de una trampa electromagnética, un único ion que se encuentra confinado en dicha trampa. El objetivo inicial era mejorar las prestaciones en lo que se refiere a sensibilidad y precisión, en espectrometría de masas de alta precisión, para aplicarla sobre elementos súper-pesados (Z>104), producidos en reacciones de fusión-evaporación, con tasas de producción muy bajas, y/o para aplicar el método sobre algunos isótopos específicos (187Re, 187Os) para contribuir, junto a otros experimentos de desintegración beta, a medir la masa del (anti)neutrino electrónico [1]. La técnica propuesta podría sustituir otra bien establecida (aunque no trivial), que amplifica la corriente inducida por medio de circuitos resonantes con la frecuencia de movimiento del ion [2], y que ha dado lugar a resultados de gran relevancia científica [3,4]. No obstante, dicho método no se ha demostrado con iones que tienen relaciones masa-carga elevada, debido a limitaciones técnicas que reducen el cociente señal-ruido. La técnica propuesta se basa en una idea original de D.J. Heinzen y D.J. Wineland [5], publicada en 1990 y no materializada hasta la fecha. Dos iones confinados cada uno de ellos en una trampa electromagnética, interaccionarán a través de las corrientes que inducen si sus electrodos están comunicados por medio de un hilo conductor (o superconductor). Para ello, los iones deben oscilar con frecuencias en torno a 100-300 kHz, iguales en un nivel por debajo del hertzio, cuando además dicho control depende de fuentes de alimentación de voltaje continuas, que pueden llegar a estabilidades de 10-7. Asumiendo que existe acoplamiento, podríamos conocer la masa-carga de cualquier ion Xa+ (o Xa-), que moviéndose con una energía del orden de 10-3 eV, generará una fuerza oscilante sobre el otro ion (40Ca+) que previamente ha sido enfriado con láseres hasta la temperatura de ~1 mK. Una ventaja significativa que se espera obtener de utilizar esta técnica es que debido a que la amplitud de oscilación del ion 40Ca+ enfriado es inferior a la temperatura de un ion enfriado de forma resonante con un circuito a 4 K, se logra una mejora evidente en sensibilidad si cualquier perturbación por pequeña que fuese es visible y con ello, una mejora en exactitud hasta alcanzar el límite cuántico. Pero el efecto de “conexión” entre dos iones no se ha demostrado hasta la fecha, cuando los iones están en trampas distintas. Para conseguir la conexión entre iones hay que reducir las dimensiones de las trampas a utilizar, respecto al tamaño de las utilizadas en física nuclear, y emplear técnicas de micro-mecanizado. Además existe un aumento de energía no despreciable (en torno a 0.2 μeV/s medido en una trampa específica en Granada) cuando los láseres no actúan (momento de interacción entre los iones), que se debe reducir, y por lo que el sistema debe funcionar a 4 K. El grupo de D.J. Wineland en NIST (Boulder) publicó en 2011 la conexión entre iones en la misma trampa de radiofrecuencia pero separados por un pozo de potencial [6] y el grupo de H. Häffner en Berkeley [7] está trabajando en ello, también con trampas de radiofrecuencia, para conseguir lo que sería un hito en el marco de la electrónica cuántica. En Granada, el hecho de utilizar trampas Penning para su uso en espectrometría de masas con elemento súper-pesados [8], conllevará a un menor calentamiento del ion, pero el campo magnético de 7 tesla origina un mayor número de transiciones en el proceso de enfriamiento. Para enfriar el ion de 40Ca+ en ausencia de campo magnético, sólo son necesarios dos láseres: uno de longitud de onda de 397 nm, para acceder a la transición dipolar eléctrica 4s2S1/2→4s2P1/2, y otro con longitud de onda de 866 nm, para bombear del estado 3d2D3/2, al que decae en el proceso de enfriamiento con una probabilidad del 7%, y continuar en el ciclo de enfriamiento. El confinamiento en 7 Tesla, origina un desdoblamiento de niveles por efecto Zeeman en primer y segundo orden, además de mezcla de estados en la estructura fina, que hacen necesarios 12 láseres para el proceso de enfriamiento. Para superar estos obstáculos y poder llegar al objetivo final ha sido necesario montar tres experimentos con trampas y uno de criogenia. En esta contribución hablaré de cómo hemos ido construyendo este laboratorio de trampas de iones, el único en España de esta naturaleza, con una financiación total de 3 millones de euros. Mostraré las distintas trampas y sistemas de láseres, cómo solventamos los aspectos técnicos más relevantes expuestos con anterioridad, y los resultados obtenidos [9-14] y sus implicaciones en física nuclear, en relación a experimentos en el GSI de Darmstadt y a la futura instalación MATS en FAIR, así como en el marco de las tecnologías cuánticas. Concluiré mostrando las previsiones para alcanzar el objetivo final de conexión entre iones. Agradecimientos Este laboratorio ha sido financiado por el Consejo Europeo de Investigación (ERC StG 278648-TRAPSENSOR) junto con los proyectos MINECO/FEDER FPA2012-32076, FPA2015-67694-P, UNGR10-1E-501 y UNGR13-1E-1830, y Junta de Andalucía/FEDER IE_57131. También quiero agradecer al MINECO, a la Junta de Andalucía, a la Universidad de Granada y al Centro Nacional de Partículas Astropartículas y Nuclear por la financiación recibida a través de los programas de empleo juvenil, intensificación de la investigación y apoyo técnico. Quiero agradecer de manera especial a los estudiantes-compañeros que han pasado por este proyecto y que han dejado su huella en los sistemas construidos/estudiados, en particular a Juanma, Pablo, Carlos, Ernesto, Martín y Jaime, así como a los compañeros-estudiantes y doctores que trabajan en la actualidad: Fran, Manuel Jesús, Raúl, Jesús, Stefan y Joaquín. Finalmente agradecer a los colaboradores del GSI-Darmstadt, la Universidad de Mainz, la Universidad de Hannover y la Universidad del País Vasco. Referencias [1] D. Rodríguez, Appl. Phys. B. 107 (2012) 1031 [2] R. S. Van Dyck Jr. et al., Int. J. Mass Spectrom. 251 (2006) 231 [3] S. Ulmer et al., Nature 524 (2015) 196 [4] S. Sturm et al., Nature 506 (2014) 467 [5] D. J. Heinzen, D. J. Wineland, Phys. Rev. A. 42 (1990) 2977 [6] K.R. Brown et al. Nature 471, (2011) 191 [7] N. Daniilidis et al., J. Phys. B 42 (2009) 144012 [8] M. Block et al., Nature 463 (2010) 785 [9] J. M. Cornejo et al., Nucl. Instrum. Methods Phys. Res. B, 317 (2013) 522 [10] J. M. Cornejo et al., Rev. Sci. Instrum. 86 (2015) 103104 [11] J.M. Cornejo, D. Rodríguez, Nucl. Instrum. Methods Phys. Res. B, 376 (2016) 288 [12] J. M. Cornejo et al., Int. J. Mass Spectrom. 410C (2016) 22. [13] F. Domínguez et al., artículo bajo revisión. [14] F. Domínguez et al., contribución a este congreso.
        Speaker: Dr. Daniel Rodríguez (Universidad de Granada)
      • 15:25
        Caracterización de un ion de 40Ca+ enfriado por láser como detector en experimentos de espectrometría de masas de alta precisión 15m
        En la espectrometría de masas mediante trampas Penning existe una variedad de técnicas de medida de alta precisión con múltiples aplicaciones de relevancia en física fundamental, como por ejemplo la comprobación de leyes físicas o la determinación de propiedades fundamentales de partículas elementales [1,2]. La técnica más sensible, i.e., la única que permite detectar un único ion confinado en la trampa, es la de corrientes inducidas (IIC), donde la detección se realiza utilizando circuitos LC o SQUIDs -resonantes con alguna de las frecuencias propias de movimiento del ion en la trampa-. Las medidas de masa más precisas se han llevado a cabo en experimentos donde se emplea la técnica IIC con iones que tienen una relación masa-carga baja o intermedia [3], pero aún no se ha mostrado su aplicabilidad con los elementos superpesados (Z ≥ 104) [4]. Con el objetivo de poder medir la masa de elementos de interés en esta zona de la carta de núcleos, se ha propuesto un método alternativo de detección [5] que actualmente se encuentra en desarrollo en el Laboratorio de Trampas de Iones de la Universidad de Granada. El proyecto TRAPSENSOR se basa en sustituir el sistema de detección electrónica por un ion de 40Ca+ enfriado por láser, que actúa como sensor óptico. Esta detección óptica consiste en la monitorización de la amplitud del movimiento axial del ion de 40Ca+ a partir de la recolección de los fotones de fluorescencia emitidos por el mismo. El ion cuya masa queremos medir y el ion sensor están conectados mediante un electrodo común que permite acoplar sus movimientos a través de las corrientes inducidas en el mismo. Esta idea, inicialmente propuesta en la Ref. [6], se ha llevado a cabo acoplando dos especies iónicas en una misma trampa a través de la interacción de Coulomb entre los dos iones confinados en el mismo pozo de potencial [7] o en pozos de potencial distintos [8], previamente enfriados hasta el mismo estado cero de energía. Sin embargo, todavía no se han acoplado dos iones confinados en trampas distintas. En la Universidad de Granada, el objetivo final es este acoplamiento en un sistema de dos microtrampas (descrito y caracterizado en la Ref. [9]) en el seno de un campo magnético de 7 T. Como paso previo al acoplamiento, se ha caracterizado el ion de 40Ca+ como sensor de señales eléctricas midiéndose la variación de la señal de fluorescencia del ion confinado en una trampa de radiofrecuencia con simetría rotacional [10] al aplicar un campo eléctrico dipolar oscilante, tratando de simular el efecto producido por un ion en una trampa contigua. Este estudio en la trampa de radiofrecuencia nos permite estimar la sensibilidad del sistema final a la excitación mediante campos eléctricos. En la Fig.1 se muestran las imágenes de fluorescencia obtenidas para dos casos particulares: en ausencia de excitación y cuando se aplica un campo eléctrico dipolar cercano a la frecuencia del movimiento axial del ion en la trampa. En ausencia de excitación, la proyección de la imagen de fluorescencia en el plano axial resulta en una distribución gaussiana con una desviación típica de 3 μm, de la que es posible inferir la temperatura axial del ion en el límite Doppler usando el Teorema de equipartición [11]. Para una excitación continua y en presencia de los láseres de enfriamiento, el ion alcanza un estado estacionario que consiste en una oscilación amortiguada y forzada de amplitud constante, cercana a 20 μm. Para caracterizar la sensibilidad del ion de 40Ca+ a señales eléctricas aplicadas, tales como las generadas por un ion, hemos estudiado la amplitud de oscilación en el estado estacionario del ion en función de la frecuencia del campo aplicado [12]. En esta contribución presentaremos los resultados obtenidos y las mejoras previstas a corto y medio plazo. Uno de los objetivos a medio plazo es mejorar las prestaciones del sistema óptico que permitan mejorar la sensibilidad y reducir la temperatura del ion añadiendo otro mecanismo de enfriamiento. En paralelo se investigará el enfriamiento del ion en una trampa Penning de 7 T. Figura 1. Imágenes de fluorescencia del ion para los casos sin campo externo aplicado (izquierda) y aplicando un campo dipolar resonante con el movimiento del ion (derecha). Las imágenes se han adquirido a través de una cámara EMCCD y un sistema óptico que permite una magnificación de un factor 7. Este proyecto está financiado por el Consejo Europeo de Investigación (ERC StG 278648-TRAPSENSOR) junto con los proyectos MINECO/FEDER FPA2012-32076, FPA2015-67694-P, UNGR10-1E-501, FIS2015-69983-P, UNGR13-1E-1830 y Junta de Andalucía/FEDER IE_57131. F.D. agradece al MINECO y a la Universidad de Granada la financiación recibida a través del Plan de Empleo Juvenil. S.S. y J.J.D.P agracen a la Universidad de Granada la financiación recibida a través del Plan Propio de Investigación (programa 24-Intensificación de la Investigación). Referencias [1] S. Ulmer et al., Nature 524 (2015) 196. [2] S. Sturm et al., Nature 506 (2014) 467. [3] R. S. Van Dyck Jr. et al., Int. J. Mass Spectrom. 251 (2006) 231. [4] M. Block et al., Nature 463 (2010) 785. [5] D. Rodríguez, Appl. Phys. B. 107 (2012) 1031. [6] D. J. Heinzen, D. J. Wineland, Phys. Rev. A. 42 (1990) 2977. [7] P. O. Schmidt et al., Science 309 (2005) 749. [8] K. R. Brown, et al., Nature 471 (2011) 196. [9] J. M. Cornejo et al., Int. J. Mass Spectrom. 410C (2016) 22. [10] J. M. Cornejo et al., Rev. Sci. Instrum. 86 (2015) 103104. [11] D. Leibfried et al., Rev. Mod. Phys. 75 (2003) 281.
        Speaker: Mr. Francisco Domínguez González (Universidad de Granada)
      • 15:40
        Development of an ultrafast X-ray laser-plasma source 15m
        We report the development of a fast rotating target system to produce ultrashort incoherent X-ray pulses from Bremsstrahlung. These ultrashort X-ray pulses are produced in the laser-plasma interaction of solid metallic targets with 35fs, 1mJ pulses centered at 800nm of a 1kHz repetition rate Ti:sapphire laser. We describe the experimental issues of the system such as the stability of the rotatory target or laser focusing with a small Rayleigh length (<20μm) which can modify the laser intensity on target and change the characteristics of the X-ray source. We also report the X-ray spectra analysis of different metallic targets. We observe the X-ray source has a broad Maxwellian-like distribution with temperatures of around 10–120keV. These kind of X-ray sources could be used for advanced X-ray imaging such as absorption or phase contrast tomography.
        Speaker: Mrs. Lucía Martín (Universidad de Santiago de Compostela)
        Slides
      • 15:55
        Preliminary Results on 64Se beta decay experiment at RIKEN Nishina Center 15m
        Spin-isospin excitations can be studied by beta decay and charge exchange reactions in mirror nuclei, shedding light on mirror symmetry, hence we can compare our results on the beta decay of proton-rich nuclei with the results of charge exchange experiments when appropriate targets for the mirror nuclei are available [1]. Accordingly we have performed experiments at GSI and GANIL to study Tz =-1 [2] and Tz =-2 [3,4] nuclei respectively where it became clear that the study of heavier, more exotic systems, demands beam intensities available only at the RIKEN Nishina Center. In this work we present the first experimental observation of the beta-delayed protons in the decay of the Tz =-2 64Se.
        Speaker: Mr. Pablo Aguilera (Instituto de Física Corpuscular de Valencia)
        Slides
      • 16:10
        Medida de vidas medias de estados excitados en los núcleos 136Te y 137Te en la campaña EXILL-FATIMA 15m
        El estudio de núcleos exóticos ricos en neutrones en torno a los doblemente mágicos 78Ni y 132Sn proporciona información relevante sobre las energías de partícula independiente así como de desarrollo de efectos colectivos cerca de los cierres de capa nucleares. La investigación de estos núcleos exóticos puede clarificar las inesperadas modificaciones de la estructura de capas que se produce en estas regiones, y conocer en mejor medida las interacciones efectivas entre nucleones, así como la validación de modelos teóricos. En la región cercana al 132Sn los núcleos de telurio son una buena ejemplo, puesto que poseen dos protones fuera del cierre de capas Z=50, y su estructura puede ser explicada mediante el acoplamiento de una pareja de protones al 132Sn. La colectividad del 136Te se estudió por primera vez mediante reacciones de excitación coulombiana [1], obteniéndose una probabilidad reducida de transición B(E2; 2+0+) de 208(29) e2fm4. Este valor es mucho menor de lo esperado y no encaja con la sistemática de la zona, en la que se espera un incremento progresivo de las tasas de transición a medida que nos alejamos de N = 82. En este caso el valor B(E2; 2+0+) es muy similar al del 134Te (N=82) y además los cálculos de modelo de capas tampoco lo reproducen con exactitud. Posteriores estudios de desintegración beta [2] midieron la vida media del estado 2+ a través del la técnica ATD [3], proporcionando probabilidad reducida de transición B(E2; 2+0+) = 250(50) e2fm4, valor que encaja mejor con la sistemática de la zona y con los cálculos teóricos. Por tanto se precisa de una clarificación de este valor para la transición 2+->0+ y, si es posible, ampliar las medidas de probabilidades reducidas a las transiciones E2 entre otros estados de la banda del estado fundamental. En este trabajo presentamos la investigación de varios núcleos de Te ricos en neutrones mediante medidas de espectroscopia gamma y de coincidencias ultrarrápidas. Los experimentos se realizaron en el ILL (Institut Laue-Langevin) de Grenoble Francia, empleando el espectrómetro mixto EXILL-FATIMA, que es una estructura mixta de 8 clovers de Ge y 16 detectores de LaBr3(Ce) [4], que aúna la buena resolución energética y eficiencia de los detectores de germanio, con la excelente resolución temporal de los cristales centelleadores. Los núcleos de interés se produjeron mediante fisión inducida por neutrones fríos sobre blancos de 235U y 241Pu. En esta comunicación presentamos el análisis de datos y los valores obtenidos para las vidas medias de los estados excitados de 136Te, comparándolos con los valores medidos previamente para la vida media del estado 2+ [2] y la intensidad B(E2; 2+0+), ampliándolos a otros niveles, y enmarcándolos en la sistemática de la zona. Se proporciona además información sobre las intensidades de las transiciones electromagnéticas al estado fundamental del núcleo impar 137Te, junto con valores preliminares de las vidas medias de los estados excitados.
        Speaker: Mrs. Victoria Vedia (Universidad Complutense Madrid (UCM))
        Slides
      • 16:25
        Línea de neutrones en el CNA 15m
        La física de neutrones experimental juega un papel fundamental en diversos campos como física de materiales, tecnología nuclear, astrofísica y física médica. En el CNA nos hemos propuesto desarrollar una línea de neutrones versátil capaz de producir haces de neutrones para diferentes aplicaciones. Así hemos proporcionado neutrones térmicos (
        Speaker: Mr. Miguel Macías Martínez (CNA (Centro Nacional de Aceleradores), Univ. Sevilla)
        Slides
      • 16:40
        DENSITY DEPENDENCE OF THE SYMMETRY ENERGY FROM NEUTRON SKIN THICKNESS, PARITY-VIOLATING ELASTIC ELECTRON SCATTERING AND ELECTRIC DIPOLE POLARIZABILITY 20m
        The nuclear symmetry energy J is an essential quantity in nuclear physics and astrophysics because it governs important properties of small entities like atomic nuclei and of very large objects as neutron stars. The nuclear symmetry energy represents the energy cost of changing protons in neutrons in symmetric nuclear matter. The symmetry energy can be estimated as a function of the density as the difference between the energy per particle in pure neutron matter and in symmetric nuclear matter. The behaviour of the symmetry energy as a function of the density is basically ruled by the its slope respect to the density computed at saturation L. Although the symmetry energy and its slope are not strictly observables, many different experiments have been devised to estimate these quantities using strong and electromagnetic probes [1]. We will discuss here our predictions of the symmetry energy and its slope obtained from three different experiments. First, we estimate the slope of the symmetry energy L from experimental data of the neutron skin thickness extracted from antiprotonic atoms [2-5]. Second, we discuss the ability of parity-violating elastic electron scattering at low momentum transfer to obtain information on the neutron skin thickness in 208Pb and to constraint the density dependence of the nuclear symmetry energy [6-7]. Finally, we compare the experimental electric dipole polarizability obtained via polarized proton inelastic scattering at forward angles in 208Pb, 120Sn and 68Ni [8,9] with the corresponding theoretical RPA calculations, which allow to estimate the symmetry energy J and its slope L. All these experiments provide different constraints on the slope L of the symmetry energy but the corresponding values have a considerable overlap in a range around , in reasonable agreement with other estimates that use different observables and methods to extract L. A global review about our work on these three topics can be found in Refs [10,11]. Referencias [1]. Bao-An Li, Xiao Han, Phys. Lett. B727 (2013) 276. [2]. M. Centelles, X. Roca-Maza, X. Viñas, M. Warda, Phys. Rev. Lett. 102 (2009) 122502 . [3]. M. Warda, M. Centelles, X. Roca-Maza, X. Viñas, Phys. Rev. C80 (2009) 024316. [4]. M. Warda, M. Centelles, X, Roca-Maza, X. Viñas, Phys. Rev. C81 (2010) 054309. [5]. M. Warda, M. Centelles, X. Viñas, X. Roca-Maza, Phys. Rev. C89 (2014) 064302 . [6]. M. Centelles, X. Roca-Maza, X. Viñas, M. Warda, Phys. Rev. C82 (2010) 054314. [7]. X. Roca-Maza, M. Centelles, X. Viñas, M. Warda, Phys. Rev. Lett. 106 (2011) 252501. [8]. X. Roca-Maza et al, Phys. Rev. C88 (2013) 024316 . [9]. X. Roca-Maza et al, Phys. Rev. C92 (2015) 064304 . [10]. X. Viñas, M. Centelles, X. Roca-Maza, M. Warda, Eur. Phys. J. 50 (2014) 27 . [11]. X. Viñas, M. Centelles, X. Roca-Maza, M. Warda, AIP Proceedings 1606 (2013) 256.
        Speaker: Prof. Xavier Viñas (Universitat de Barcelona)
        Slides
      • 17:00
        Coffee Break 30m
      • 17:30
        Medidas de secciones eficaces de fisión con Medley en GANIL-NFS 15m
        Las secciones eficaces de fisión inducida por neutrones en los isótopos 235U y 238U se consideran estándar y, por ello, se utilizan ampliamente en medidas de flujo de neutrones. Con el objetivo de mejorar la precisión de dichos estándares y, en consecuencia, de las medidas de datos nucleares que las utilizan como referencia, estamos preparando una nueva medida experimental que relacione las secciones eficaces de dichas reacciones con la de la dispersión elástica neutrón-protón. En esta comunicación, se presentará el dispositivo experimental, basado en el uso de PPACs para detectar los fragmentos de fisión, y de detectores de silicio y cristales centelleadores para detectar los protones dispersados, y que planeamos usar en la instalación Neutrons For Science (NFS) que se está construyendo en GANIL (Francia).
        Speaker: Dr. DIEGO TARRIO VILAS (UPPSALA UNIVERSITY)
        Slides
      • 17:45
        Radiative neutron capture on 242 Pu in the resonance region at n_TOF-EAR1 15m
        The spent fuel of current nuclear reactors contains fissile plutonium isotopes that can be combined with 238U to make mixed oxide (MOX) fuels [1]. In this way the Pu from spent fuel is used in a new reactor cycle, contributing to the long-term sustainability of nuclear energy. The use of MOX fuels in thermal and fast reactors requires accurate capture and fission cross sections. For the particular case of 242Pu, there are sizable discrepancies among the cross section measurements available [2-5] all from the 70s, resulting in and uncertainty of 14% and 35 % below and above 2 keV, respectively. In this context, the Nuclear Energy Agency (NEA) recommends in its High Priority Request List (HRPL) [6] and its report WPEC-26 [7] that the capture cross section of 242Pu should be measured with an accuracy of at least 8-10% in the neutron energy range between 500 eV and 500 keV. This work presents the time-of-flight capture measurement on 242Pu, carried out at n_TOF-EAR1 (CERN) [8] featuring a white neutron beam with energies ranging from thermal to GeV. The 242Pu(n,γ) reaction on a sample containing 95 mg of extremely pure 242Pu was measured with an array of 4 C6D6 Total Energy Detectors [9]. This contribution focuses on the analysis and results in its resonance region. In this context, the unique energy resolution feature by the n_TOF-EAR1 facility has enabled to resolve, analyze and extract individual resonance parameters for more than 250 s- and p-wave resonances up to 4 keV, 180 of which are not present in JEFF 3.2. Moreover, the achieved systematic uncertainty in the capture cross section is around 4%, fulfilling the requirements of the NEA-HPRL. Last, the statistical properties of the resonances have been studied in terms of their average resonance parameters and compared to the predictions of theoretical models. A detailed version of this work can be found in Ref. [10]. Acknowledgments We acknowledge the n_TOF Collaboration. This measurement has received funding from the EC FP7 Programme under the projects NEUTANDALUS (Grant No. 334315) and CHANDA (Grant No. 605203), the Spanish Ministry of Economy and Competitiveness projects FPA2013-45083-P and FPA2014-53290-C2-2-P and the V Plan Propio de Investigación Programme from the University of Sevilla. References [1] IAEA, Status and advances in Mox fuel technology, IAEA Technical Reports Series 415 (2003) [2] F. Poortmans et al., Nucl. Phys A 207, 342-352 (1973) [3] R.W. Hockenbury et al., SP 425, 584-586 (1975) [4] K. Wisshak and F. Kaeppeler, Nucl. Sc. and Eng. 66, 363 (1978) [5] K. Wisshak and F. Kaeppeler, Nucl. Sc. and Eng. 69, 39 (1979) [6] NEA High Request Priority List http://www.nea.fr/dbdata/hprl [7] M. Salvatores and R. Jacqmin, Uncertainty and target accuracy assessment for innovative system using recent covariance data evaluations, ISBN 978-92-64-99053-1, NEA/WPEC-26 (2008) [8] C. Guerrero et al., Eur. Phys. J. A 49, 27 (2013) [9] R.Plag et al., Nucl. Instrum. and Meth. A 496, 425436 (2003) [10] J. Lerendegui, C. Guerrero et al., Phys. Rev. C (2017) (submitted)
        Speaker: Mr. Jorge Lerendegui Marco (Universidad de Sevilla)
        Slides
      • 18:00
        Neutron capture cross-section measurement of 203,204Tl and its astrophysical implications 15m
        About half of the elemental abundances between Fe and Bi are produced by the so-called s (slow) process of neutron capture reactions in AGB stars. Of particular importance are some nuclides produced during the s-process which are radioactive, with half-lives from years to Gy, so its decay process competes with the neutron capture chain: these nuclides are known as branching points. The measurement of the neutron capture cross section of these elements is crucial to determine the local abundance pattern around the branching point, which yields information of the s-process stellar environment, such as temperature, neutron density or pressure. 204Tl (T1/2=2.78 y) is a very interesting branching point. In the recurrent He-flashes of AGB stars, 204Tl can either β-decay to the s-only nuclide 204Pb or capture another neutron, thus producing 205Tl. which in some stellar environments can decay to 205Pb. On the other hand, neutron capture on 204Pb also yields 205Pb (T1/2=1.5×107 y). Therefore, the value of the 204Tl capture cross section is necessary to determine precisely the primordial 205Pb/204Pb abundances ratio, which would allow one to estimate the time span since the last s-process events that contributed to the elemental composition of the Solar System. In the year 2015, the cross section of the 204Tl(n,γ) reaction was measured for the first time ever employing four C6D6 scintillation detectors in the neutron time-of-flight facility n_TOF at CERN. The sample was a 203Tl oxide pellet enriched to 4% in 204Tl. The 204Tl total mass was 9 mg, with a total activity of 160 MBq. In this talk several aspects of this capture cross section measurement will be covered, from the experimental methods and the extraction of the cross section and other important capture reaction parameters, to the final application of the results on s-process nucleosynthesis.
        Speaker: Mr. Adrià Casanovas (UPC)
        Slides
      • 18:15
        PREMIOS ATI 25m
        Speaker: Mrs. Marta Trueba
      • 18:40
        ASAMBLEA FNUC 20m
        Speaker: Dr. Luis Fraile (Universidad Complutense de Madrid)
    • 15:00 19:20
      Plasma Physics II Aula Química Analítica (Facultad de Química (USC))

      Aula Química Analítica

      Facultad de Química (USC)

      • 15:00
        Chairperson: Dra. Nerea Bordel 5m
      • 15:05
        Electrical discharges in the upper atmosphere of the Earth and other planets of the Solar System 50m
        In this contribution, we will present an overview of the kinetic and spectroscopic aspects of the research done in our group on atmospheric electricity in planetary atmospheres. In particular, we will describe our efforts towards the understanding of lightning-driven upper atmospheric electrical discharges in the Earth, the giant planets (Saturn and Jupiter) and on Venus where the existence of lightning is still nowadays controversial since no direct optical recording of lightning is yet available though there are a number of indirect (radio emissions) results suggesting that some kind of electrical atmospheric activity could exist in Venus. In the case of the Earth, we will focus on the so called Transient Luminous Events (TLEs), which are a diversity of weakly ionized low temperature plasmas occurring in the upper atmosphere of the Earth between the thundercloud tops (15 km) and the lower ionosphere (95 km). These upper atmospheric plasmas were recorded for the first time 28 years ago (in the summer of 1989) and their occurrences are linked to the electrical (lightning) activity in the Earth troposphere (0 - 15 km). Our research tries to answer questions such as, what are the chemical and electrical impacts of TLEs in the Earth atmosphere What are the physical (kinetic and electrodynamic) mechanisms underlying the ignition of TLEs?. What are the key spectroscopic features of TLE optical emissions, how can they be detected and what can we learn by analyzing TLE optical spectra?.
        Speaker: Dr. Francisco J. Gordillo Vázquez (Instituto de Astrofísica de Andalucía (IAA - CSIC))
      • 15:55
        Study of transient lightning-driven discharges in the upper atmosphere of the Earth, Venus and giant gaseous planets 20m
        The electromagnetic field created by terrestrial lightning discharges has a chemical and an electrical impact in the plasma existent in the upper atmosphere, producing Transient Luminous Events (TLEs). Since their discover in year 1989, terrestrial TLEs have been investigated in an effort to determine their chemical impact in the upper mesosphere. In addition, the detection of possible extraterrestrial TLEs have been proposed as a tool to study lightning beyond our planet. Difficulties inherent in the study and observation of the natural plasma located in the lower ionosphere give value to the development of models. We extend previous models of the impact of quasi-electrostatic field (QE) in the terrestrial mesosphere produced by cloud-to-ground (CG) lightning discharges, providing the community with new tools to interpret observations from spacecraft. In addition, we use a Finite Difference Time-Domain (FDTD) model to investigate possible TLEs existence in the atmosphere of giant planets caused by lightning-emitted electromagnetic pulses (EMP). Finally, we apply these models to the case of Venus to investigate the mesospheric optical signature produced by hypothetical Venusian intra-cloud (IC) lightning, proposing an indirect method to determine the existence of lightning discharges in Venus from the Japanese spacecraft Akatsuki, orbiting Venus since December 2015.
        Speaker: Mr. Francisco Javier Pérez Invernón (Instituto de Astrofísica de Andalucía (IAA), CSIC)
        Slides
      • 16:15
        Fluid model for the streamer-to-leader transition in lightning channels. 20m
        One of the still not well understood phenomena involved in electric discharges is the streamer-to-leader transition. Here, as a first approach to investigate this transition, we present our recent steps modelling heating and gas expansion produced in streamer discharges, coupled to electromagnetic and air plasma chemistry. So far, we have applied this model to the mechanism of air heating and pressure perturbations present in sprite discharges, without losing sight of our final aim, i.e., to disentangle the streamer-to-leader transition in lightning channels.
        Speaker: Mr. Alejandro Malagón (Instituto de Astrofísica de Andalucía - CSIC)
      • 16:35
        Coffee break 30m
      • 17:05
        Limpieza y activación de superficies de aluminio mediante postdescargas de plasmas de microondas generadas a presión atmosférica 20m
        El aluminio es uno de los materiales más utilizados en industrias tan diversas como la automoción, la construcción o la fabricación de envases para alimentación, pero suele presentarse recubierto de una película de hidrocarburos, que evita la corrosión y la adhesión de otros materiale, y que debe ser eliminada antes de aplicar tratamientos de acabado. En este trabajo se presenta una alternativa a los proceso químicos convencionales para la limpieza y activación de superficies de aluminio basado en el uso de postdescargas de plasmas generados a presión atmosférica, cuya principal ventaja es su efectividad a distancias un orden de magnitud superiores a las consideradas hasta la fecha. Los resultados muestran un aumento de la hidrofilicidad y la energía libre superficial hasta valores de 77 mJ/m2, muy superiores a los de las muestras no tratadas que se encuentran en torno a 37 mJ/m2, siendo el mismo efectivo a distancias de hasta 5 cm. El análisis de las muestras tratadas mediante espectroscopía XPS revela que estas modificaciones se deben en parte a una reducción de la cantidad de carbono en la superficie (limpieza), así como a un aumento de los radicales OH presentes en la misma.
        Speaker: Dr. José Muñoz Espadero (Universidad de Córdoba)
      • 17:25
        Influencia del diámetro de cátodo en la caída del campo eléctrico en descargas de cátodo hueco en hidrógeno 20m
        Los plasmas a baja presión generados en régimen de glow-discharge son objeto de interés debido a sus múltiples aplicaciones, tanto en la industria como en la investigación (procesado de materiales, deposición de películas delgadas, espectroscopia, etc.). Todas estas aplicaciones requieren un profundo conocimiento del comportamiento del plasma, que puede ser estudiado tanto de manera teórica como experimental [1-4]. En el Laboratorio de Espectroscopia Láser de la Universidad de Valladolid se realizan medidas de la caída del campo eléctrico en la zona de cátodo en este tipo de descargas, puesto que esta magnitud determina en gran medida las condiciones generales de la descarga (flujo de partículas, densidades de carga, etc.). En este trabajo se presentan las medidas realizadas en una descarga de cátodo hueco en régimen glow-discharge de hidrógeno puro, con cátodos de tungsteno de 10 y 15 mm de diámetro interior. Las medidas se realizan con la misma densidad de corriente lo que permite estudiar la influencia del diámetro en la descarga.
        Speaker: Mrs. Veronica Gonzalez Fernandez (Universidad de Valladolid)
      • 17:45
        Descargas luminiscentes pulsadas como fuente de ionización de compuestos orgánicos volátiles 20m
        La detección del cáncer en etapas tempranas puede juega un papel vital para lograr tratamientos exitosos con menores complicaciones. Recientemente se ha demostrado que ciertos Compuestos Orgánicos Volátiles (COVs) pueden actuar como marcadores únicos de cáncer ya que estos compuestos son generados por las células tumorales [1]. Por esta razón, la detección de COVs en el sistema respiratorio a través de aire espirado es un tema de gran interés en este momento. En este trabajo se ha investigado la determinación e identificación de COVs mediante una fuente de descarga luminiscente pulsada (PGD, de sus siglas en inglés) con detección por espectrometría de masas del tipo tiempo de vuelo (TOFMS,). El diseño de la cámara, la distancia de introducción de muestra, potencia aplicada, presión y propiedades del pulso se optimizaron usando benceno como compuesto modelo. El modo pulsado permite la aplicación de una mayor potencia instantánea, mejorando las eficiencias de excitación y de ionización de las especies de gas. Además, la fuente PGD es un plasma dinámico que presenta procesos de ionización diferentes a lo largo del pulso aplicado, en los regímenes temporales conocidos como (prepeak, plateau y afterpeak) [2]. Del análisis de los espectros de masas medidos en los diferentes tiempos es posible obtener información molecular, de fragmentos y elemental. Además, los resultados muestran un camino prometedor para la identificación de compuestos complejos a través de la información complementaria obtenida en los espectros: simple ionización molecular y fragmentación característica del compuesto. Finalmente, se han evaluado las características analíticas de la técnica para el análisis de muestras complejas formadas por varios VOCs. Para ello se ha utilizado tanto cromatografía de gas de microextracción en fase sólida como inyección directa de muestra acopladas a PGD-TOFMS. Agradecimientos This work was supported by Ministerio de Educación y Ciencia (Spain) through the project reference “MINECO-13-CTQ2013-49032-C2-2-R” and by Principado de Asturias through Plan de Ciencia, Tecnología e Innovación 2013-2017 and FEDER through “FC-15-GRUPIN14-040” project. Referencias [1] X. Sun, K. Shao, T. Wang, Anal. Bioanal. Chem. 11 (2016) 2759-80. [2] C.L. Lewis, G.P. Jackson, S.K. Doorn, V. Majidi, F.L. King, Spectrochim. Acta – Part B. At. Spectrosc., 56 (2001), 487-501.
        Speaker: Mr. Jonatan Fandiño Rodríguez (Universidad de Oviedo)
      • 18:05
        General Meeting of the Grupo Especializado de Física de Plasmas 1h
    • 15:15 19:15
      27º Encuentro Ibérico de Enseñanza de la Física III: simposium conjunto con Enseñanza, Divulgación e Historia de la Física Aula Biología (Facultad de Química (USC))

      Aula Biología

      Facultad de Química (USC)

    • 15:15 19:15
      Energy and Sustainability III Aula Física (Facultad de Química (USC))

      Aula Física

      Facultad de Química (USC)

      • 15:15
        Efecto termoeléctrico en líquidos: Moviendo iones 30m
        En la última década, la necesidad de producir y almacenar energía de una forma económica y no dañina con el medioambiente ha llevado a una edad de oro en la síntesis y caracterización de materiales para la conversión y acumulación de energía. En este contexto, los materiales termoeléctricos son particularmente atractivos al convertir directamente un flujo de calor en corriente eléctrica permitiendo aprovechar las abundantes cantidades de calores residuales provenientes de numerosos procesos de conversión de energía (motores de combustión,…)[1]. Actualmente, existen varias líneas de investigación para lograr el objetivo de obtener sistemas termoeléctricos eficientes. En primer lugar, los basados en la termodifusión de los portadores de carga (electrones/huecos) en un conductor mediante un gradiente de temperatura que origina un voltaje dado por el coeficiente Seebeck (S = V/T). Bajo esta premisa están construidos la mayoría de los generadores termoeléctricos basados en compuestos semiconductores y semimetales [2]. Sin embargo, cabe esperar aumentar sus eficiencias (< 6 %) y solucionar inconvenientes relacionados con la toxicidad y escasez que impiden su mayor utilización [2]. Complementariamente, se está comenzando a desarrollar la investigación de la fenomenología termoeléctrica en líquidos, debido a sus altos valores de S (1-3 órdenes de magnitud mayores que en estado sólido) [3] y de sus diferentes opciones de uso (celdas termogalvánicas, supercondensadores) [4]. Al contrario que en sólidos, el gradiente térmico involucra tanto transporte de carga como de masa quedando caracterizado el gradiente de concentraciones en el estado estacionario por el coeficiente Soret [5]. Sin embargo, el que no exista un marco completo microscópico que explique la fenomenología de la termodifusión en líquidos así como su mayor dificultad experimental ha llevado a que, hasta recientemente, no hayan sido considerados en el campo de la termoelectricidad a pesar de presentar ventajas como su bajo coste y abundancia. En este trabajo se presenta el diseño, construcción y caracterización de un sencillo sistema experimental capaz de medir el coeficiente Seebeck en líquidos. Se ha investigado la influencia de la molaridad en el coeficiente Seebeck (Fig.1) de diferentes tipos de electrolitos acuosos (NaCl, KOH etc). Los valores obtenidos son mucho mayores de los que presentan los materiales en estado sólido (desde -5 mV/K hasta + 5mV/K). Se presentarán los valores de los coeficientes de difusión obtenidos a través de las curvas de voltaje y se compararán con los escasos datos existentes en la literatura. La caracterización se completa mediante medidas de conductancia para obtener los factores de potencia de los diversos electrolitos. Finalmente, se discutirán los resultados obtenidos y se propondrán vías alternativas para poder aumentar los factores de potencia por medio del uso de soluciones coloidales así como de la influencia de la luz en el proceso termoeléctrico. Los autores agradecen al proyecto MINECO-FEDER (2015-65203R) el apoyo económico y, en particular, E. Flores al Consejo Nacional de Ciencia y Tecnología de México (CONACYT) Referencias [1] J.R. Ares, I.J. Ferrer, P. Díaz-Chao, J.M. Clamagirand, S. Yoda, V. Carcelén, D. Méndez, J.F. Fernández, C. Sánchez, Revista de la Real Sociedad Española de Fisica.. 24-6 (2012) 36. [2] P. Vaqueiro, A.V. Powell, J. Mater.Chem. 20 (2010) 9577. [3] M. Bonetti, S. Nakamea, M. Roger, P. Guenoun, J. Chem. Phys. 134 (2011) 114513 [4] H. Wang, D. Zhao, Zia Khan, S. Puzinas, M.P. Jonsson, M. Berggren, X. Crispin, Adv.Electron Mater. (2017) 1700013 [5] J. Colombani, J. Bert, J. Dupuy-Philon J. Chem. Phys.110, 17 (1999) 8622
        Speaker: Mr. Jesus Garcia Ojero (Grupo MIRE, Departamento de Fisica de Materiales, Facultad de Ciencias UAM)
      • 15:45
        Preparación y caracterización de membranas híbridas Nafion®/hidróxido doble laminar (LDH) con sepiolita para aplicación en pilas de combustible 30m
        Las pilas de combustible de membrana polimérica (PEMFC) son dispositivos que representan una alternativa a los sistemas energéticos dependientes de combustibles fósiles [1]. Las principales ventajas de estos sistemas son su alta eficiencia, su bajo impacto medioambiental y la facilidad para su implantación en diversas aplicaciones tanto portátiles como estacionarias [2]. Una de las principales aplicaciones de esta tecnología está relacionada con el sector de la automoción. En la actualidad se está realizando un esfuerzo importante tanto a nivel de investigación básica como aplicada con el fin mejorar la tecnología desde múltiples puntos de vista. Así, el desarrollo de nuevos catalizadores, nuevas membranas poliméricas entre otros elementos que conforman el dispositivo de pila de combustible polimérica está llevándose a cabo con el objetivo de mejorar las condiciones de aplicabilidad enfocado siempre hacia la obtención de mejoras en la eficiencia energética total. La membrana polimérica es uno de los principales componentes de las PEMFC. A día de hoy, el Nafion® es el principal material utilizado en este tipo de aplicaciones a nivel industrial y en gran parte de la investigación. Este material tiene grandes ventajas, como son: su buena conductividad iónica a bajas temperaturas (menores a 100 °C) y sus buenas propiedades mecánicas para el uso en pila de combustible [3]. No obstante, también presenta importantes inconvenientes como son: su elevado precio, la necesidad de altos niveles de humedad para poder trabajar intercambiando protones y la imposibilidad, por lo tanto, de hacerlo cuando las temperaturas son mayores de 100ºC [4]. El trabajo por debajo de hecho de 100 °C tiene varias desventajas; la necesidad de uso de catalizadores nobles capaces de llevar a cabo las reacciones de oxidación de hidrógeno y reducción de oxígeno con cinéticas adecuadas, la necesidad de alimentar el dispositivo con hidrógeno puro como combustible sin impurezas de CO, S, etc. con la consiguiente pérdida de eficiencia del dispositivo. En este trabajo se presentan membranas compuestas basadas en Nafion® y modificadas con la incorporación en su estructura de hidróxido doble laminar (LDH) Mg2Al hibridado y además con sepiolita. El objetivo a alcanzar con estos materiales, esta relacionado con poder aumentar la temperatura de operación de las pilas de combustible por encima de los 100 °C manteniendo una elevada conductividad iónica en las membranas. La hibridación del LDH con la sepiolita será la encargada de aumentar la retención de agua en las membranas, permitiendo de este modo que esta se libere por encima de los 100 °C, manteniendo e incluso mejorando la conductividad de la membrana a estas temperaturas. La síntesis de las membranas se lleva a cabo mediante el proceso de casting que consiste en la dispersión y mezcla de los materiales en una disolución de dimetilacetamida (DMAc) y el calentamiento de ésta obteniendo finalmente una membrana homogénea para su posterior estudio. Se han obtenido diferentes membranas con diversos porcentajes de LDH and sepiolita con la finalidad de e analizar el efecto de los aditivo e intentar diseñar la composición óptima para la aplicación descrita anteriormente. La caracterización físico-química de las membranas sintetizadas se lleva a cabo mediante diferentes técnicas: microscoscopía electrónica de barrido (SEM), espectroscopía infrarroja (FTIR) con el fin de conocer la composición y morfología de las mismas. Además, se han realizado ensayos de termogravimetría (TGA) para tratar de conocer las prestaciones de las hibridaciones a temperaturas superiores a 100 °C así como la temperatura de operación óptima de los distintos materiales. Teniendo en cuenta su aplicación futura, se realizan medidas de las propiedades mecánicas de las membranas obteniendo el módulo de Young, de modo que se puede conocer la manejabilidad de estos materiales como electrolitos sólidos para pilas de combustible de membrana polimérica. Por último, se realizan medidas de absorción de humedad de las membranas a diferentes temperaturas, obteniendo datos relevantes sobre la capacidad de captación de agua. Se llevan a cabo medidas de conductividad iónica de las membranas modificadas con el fin de conocer la aplicabilidad como intercambiadores iónicos a diferentes temperaturas. Mediante medidas de impedancia de los electrolitos, puede analizarse la variación de la conductividad con la temperatura para cada una de las membranas en las distintas composiciones y compararlas con el Nafion® sin modificar. De este modo, se puede realizar una primera aproximación del funcionamiento que presentarán estos materiales en la aplicación final. Por último, se realizan medidas en pila de combustible con H2/ O2 como reactivos con la finalidad de conocer el rendimiento de los dispositivos con las diferentes membranas sintetizadas y se comparan con membranas de Nafion®. La figura 1 muestra las curvas de polarización y densidad de potencia de una de las membranas sintetizadas a tres diferentes temperaturas.
        Speaker: Dr. Ricardo Escudero Cid (Departamento de Química Física Aplicada, Universidad Autónoma de Madrid)
      • 16:15
        Finite Element Analysis of Nanopores in Capacitive Energy Extraction Based on Double Layer Expansion (CDLE) 30m
        Capacitive energy extraction based on double layer expansion (CDLE) is a new method devised for extracting energy from the exchange of fresh and salty water in porous electrodes. First suggested by D. Brogioli, it is enclosed in a group of emergent technologies jointly known as Capmix methods. The CDLE technique is based on the fact that the capacitance of the electric double layer (EDL) strongly depends on the ionic contents of the medium. If a metal/solution interface is externally charged in the presence of high ionic strength, and discharged in low ionic strength, it might be possible to obtain a net amount of energy. In order to increase the charge transfer, electrodes made of micro- or nano-porous carbon particles can be used because of their huge surface area. The behaviour of the fluid flow field, the electric potential field and the ionic distributions inside the nanopores during an entire CDLE cycle must be correctly determined to gain a complete understanding of the physics involved and to optimize the energy extraction per cycle. We have performed a finite element analysis that computes the time-dependent full coupling between the Navier-Stokes, the Poisson and the mass transport (diffusion, convection and electromigration of ions) equations. From the numerical solutions, we have been able to obtain the relevant time scales of the processes that take place inside the nanopores and to compare them with experimental results. As an example, the figure shows the time evolution of the ionic sodium concentration in a representative pore just after exchanging the solution in contact with the pore mouth from sea water to river water. Note that the expansion of the EDL has started in the region close to the mouth of the nanopore and that it is extending towards its interior.
        Speaker: Dr. Emilio Ruiz-Reina (Departamento de Física Aplicada II, Universidad de Málaga)
      • 16:45
        Coffee Break 30m
      • 17:15
        Energías renovables y generación distribuida. 30m
        La ponencia analiza el papel de las energías renovables en la generación distribuida, focalizando su atención en los aspectos vinculados al autoconsumo y a las instalaciones de baja y media potencia, tanto en entornos urbanos como en el medio rural. Se expondrán varios ejemplos de trabajos de investigación donde la aplicación de tecnologías de información geográfica es determinante para el desarrollo de modelos de autoconsumo en particular y de integración de las energías renovables en general.
        Speaker: Dr. JAVIER DOMINGUEZ (CIEMAT)
      • 17:45
        Dependencia estructural y electrónica de las interfases polares y no polares entre el CuGaS2/CuAlSe2 y CuGaS2/ZnSe 30m
        El estudio de los fenómenos físicos involucrados en las interfases entre los diferentes semiconductores que pueden considerarse para formar una célula solar, ha sido objeto de creciente actividad durante los últimos años [1,2]. Particularmente, en las células solares de calcopirita la unión entre el CuGaS2 y la capa “buffer” (CdS o ZnSe) está formada por materiales con diferentes anchuras de banda prohibidas, diferentes afinidades electrónicas y diferentes posiciones energéticas del nivel de Fermi. La consecuencia de estas diferencias se refleja en la discontinuidad de la banda de valencia y conducción, además de la formación de un momento dipolar en la interfase que genera un escalón en el potencial electrostático. De acuerdo a un resultado previo [3], el alineamiento de bandas de las interfases entre el CuGaS2/CuAlSe2 y CuGaS2/ZnSe muestran las características adecuadas para el diseño y desarrollo de células solares de película delgada. Los resultados sugieren que las interfases entre ellos afectan a la eficiencia de conversión en células solares [4]. Sin embargo, las complicaciones teóricas que se derivan de las complejas interacciones entre los enlaces de las interfases y el desajuste de la red entre los compuestos han impedido el desarrollo de modelos analíticos generales capaces de predecir con precisión las magnitudes en la discontinuidad de las bandas [5]. El gran desajuste de la red entre el CuGaS2 y el material de contacto (CuAlSe2 ~ 6% y ZnSe ~ 5%) y el alineamiento de bandas del tipo II entre las dos interfases, han motivado este estudio de las heteroestructuras con CuGaS2, debido a que el tipo de alineamiento va acompañado de una separación de las carga, lo cual es ventajoso para este tipo de células solares. Haciendo uso de la metodología de primeros principios, combinando la teoría del funcional de la densidad (DFT) y cálculos cuánticos (funcionales híbridos), obtuvimos los alineamientos de bandas de las heterouniones entre el CuGaS2 y el CuAlSe2 y ZnSe. Para el alineamiento de las bandas de energía, se construyó un modelo de las superficies en contacto y se utilizó un método de alineamiento basado en el potencial electrostático promedio [6]. Las cuatro superficies de contacto estudiadas corresponden a dos tipos de orientaciones polares (001) y (1 ̅1 ̅2 ̅) y dos orientaciones no polares (110) y (102) (Figura 1). De acuerdo al modelo empleado, la dependencia de las propiedades de la interfase respecto a la orientación y la terminación química, no modifica sustancialmente el tipo de alineamiento de bandas que presenta cada interfase. Se agradecen los recursos informáticos y asistencia técnica proporcionada por el Centro de Supercomputación y Visualización de Madrid (CeSViMa) y al Laboratorio Nacional de Supercómputo del Sureste de México (LNS1).
        Speaker: Dr. Pablo Palacios (Universidad Politécnica de Madrid)
      • 18:15
        Impacto de la Implantación de Vanadio y vacantes de Silicio en la Estructura Cristalina y Propiedades de Absorción Ópticas del Silicio 30m
        Este trabajo presenta un estudio de la estructura cristalina y las características de absorción óptica de materiales basados en silicio implantados con vanadio mediante cálculos de la teoría funcional de la densidad (DFT) y de quasi-partícula. Nuestros resultados señalan que la estructura electrónica del silicio puede modificarse adecuadamente a través de la implantación en V para mejorar la absorción por debajo del bandgap (sub-bandgap). La Teoría Funcional de Densidad (DFT) se ha utilizado para estudiar las estructuras cristalinas, las estabilidades y las propiedades electrónicas de los compuestos de silicio implantados en V. Debido a que los defectos son comunes en los materiales naturales y pueden modificar las propiedades eléctricas y ópticas, también se estudian diferentes modelos de silicio implantado con V en presencia de Vacantes de Si. Por último, para hacer frente a la sub-estimación en el bandgap de los métodos DFT, se realizaron cálculos más precisos a través de la aproximación G0W0, lo que da una clara mejoría en los bandgaps calculados. En resumen, nuestros resultados muestran que las características de absorción de silicio se puede extender hasta la región infrarroja a través de la adición de sub-gap transiciones a través de bandas de vanadio situado en el bandgap del Si.
        Speaker: Dr. Gregorio García (ETSI Telecomunicación. Universidad Politécnica de Madrid)
      • 18:45
        Solar cell architectures by combining graphene and carbon nanotubes with silicon 30m
        There is intensive efforts in exploring innovated solar cell structures with high performance and cost-effective manufacturing methods. In this frame, emerging competitive technologies include the combination of inexpensive materials with conventional silicon wafers silicon. We will present graphene, carbon nanowires-Si junction solar cells with high efficiencies by coating an antireflection layer. We have used a titanium oxide coating because significantly inhibits light reflectance from the Si surface, resulting in an enhanced short-circuit current and external quantum efficiency. Solar cell characteristics were tested by a source meter, we have obtained the J-V curves (0- 0.6 eV) and the IPCE (300- 1200 nm). The light-to-electricity conversion in the solar cells involves several key steps, including light absorption, charge separation and carrier collection. The light absorption step determines how much fraction of incident photons can be absorbed by the semiconductor and the excitation of charge carriers. We have also measured the surface roughness because light reflection from polished silicon could be even 36%, resulting in significant energy loss in the light absorption stage, for this reason a suitable aspect ratio is required. The surface roughness has checked by electron irradiation the samples as a function of the incidence angle of the primary electrons (0-1000eV).
        Speaker: Prof. Isabel Montero (CSIC)
    • 15:15 19:15
      Enseñanza, Divulgación e Historia de la Física: simposium conjunto con el 27º Encuentro Ibérico de Enseñanza de la Física Aula Biología (Facultad de Química (USC))

      Aula Biología

      Facultad de Química (USC)

      • 15:15
        Enseñar a pensar como objetivo prioritario de la enseñanza (también de la Física) 45m
        Speaker: Prof. Luis Ignacio García
      • 16:00
        Gravisolitones y ondas gravitacionales no lineales 30m
        La astronomía de ondas gravitacionales ha nacido gracias a la observación de dos ondas gravitacionales originadas por la fusión de dos parejas de agujeros negros de masa estelar. Observadas por los dos detectores de Advanced LIGO a finales del año 2015, fueron la gran noticia científica del año 2016 (Science’s 2016 Breakthrough of the Year). La enseñanza y la divulgación científica de esta noticia siempre se centran en los aspectos lineales de la propagación de las ondas gravitacionales en un espaciotiempo plano. Sin embargo, tanto en su fuente, la fusión de objetos compactos, como en rigor en su esencia, se trata de un fenómeno fuertemente no lineal. En esta comunicación mi objetivo es reclamar la atención a este hecho al hilo de historia.
        Speaker: Dr. Villatoro Francisco R. (Universidad de Malaga)
        Slides
      • 16:30
        DRAMATIZAÇÃO: "A VIDA DE GALILEU EM (MAIS DE) DOIS ATOS" 15m
        Atividade (e respetivo estudo de caso) realizada com professores e alunos, no contexto da História da Ciência, associada às principais descobertas de Galileu, que conduziram ao estabelecimento da Ciência Moderna. A dramatização desenrola-se em vários atos. Inicia-se com a declamação de uma poema de António Gedeão (pseudónimo de Rómulo de Carvalho, Linhas de Força, feito em homenagem a Galileu. Em seguida, enfatizam-se algumas das suas principais descobertas efetuadas nos anos de 1609 e 1610, nomeadamente a descoberta das fases de Vénus e das quatro principais luas de Júpiter, hoje designadas por "Satélites Galileanos". Depois, é recriado o julgamento de Galileu pelo Tribunal do Santo Ofício, bem com a carta de abjuração. Apresentam-se ainda os resultados dos estudos efetuados através de inquéritos e questionários, tendo em a avaliação da aceitação e pertinência da atividade, bem como a avaliação das aprendizagens significativas apreendidas pelos alunos participantes no processo.
        Speaker: Prof. Jorge António (Agrupamento de Escolas de Montijo)
      • 16:45
        El enlace químico y la mecánica cuántica: cuando la física explicó lo que los químicos llevaban 70 años contando 15m
        La explicación mecanocuántica del enlace químico es uno de los puntos de encuentro más importantes entre la física y la química. En esta comunicación se analizan los orígenes e historia, así como algunas consecuencias científico-docentes de esta conjunción. Se mencionan las dos teorías más significativas, TEV y TOM, y se repasa el currículo LOMCE en lo que atañe a esta cuestión.
        Speaker: Prof. Jesús María Arsuaga (Universidad Rey Juan Carlos)
      • 17:00
        Coffee break 30m
      • 17:30
        Aprender física com o meu vizinho: o modelo colaborativo da Universidade de Harvard 45m
        Nos últimos anos, estudos internacionais revelaram que os alunos aprendem melhor com os seus colegas - Peer Instruction, do que com os professores. Algumas razões explicam este fenómeno, mas uma das mais importantes é o facto dos alunos estarem mentalmente ativos quando discutem com os seus pares. Na metodologia Team & Project-based Approach (T&PBA), desenvolvida e implementada por Eric Mazur na Universidade de Harvard, o ambiente de aprendizagem consiste em seis atividades diversificadas, totalmente colaborativas (Peer Instruction) e segundo o modelo de aulas invertidas (Flipped Classrooms) [1], [2]. Neste ambiente há breves momentos de discussão por parte do professor e não existe exame final, apesar dos alunos serem continuamente avaliados e receberem feedback constante. Esta metodologia tem vindo a ganhar expressão em todo o mundo, tendo sido já adotada em vários países, em Universidades de referência, e em diferentes áreas. Referências [1] M. Eric, Peer Instruction: a user’s manual, 2ª ed., Prentice Hall, Inc., 1997. [2] N. Alan, Who Owns the learning, 1ª ed., Solution Tree, United Kingdom, 2012.
        Speaker: Dr. Ana Rita Lopes Mota (Departamento de Física e Astronomia, Universidade do Porto)
      • 18:15
        La primera iluminación pública en España: de las pilas Bunsen a las pilas de combustible 15m
        Introducción Cuando se celebra la XXXVI Bienal de Física en Santiago de Compostela se cumplen casi 170 años de un evento científico muy relevantes del siglo XIX en España, llevado a cabo por el científico gallego Antonio Casares Rodríguez. En la noche del 2 de abril de 1851 procedió a la iluminación mediante un arco voltaico de un edificio público por primera vez en España en esta misma ciudad, Santiago de Compostela, en el claustro del antiguo edificio central de la Universidad (hoy Facultad de Geografía e Historia) [1]. La realización de esta demostración pública en esta ciudad supuso un gran efecto desde el punto de vista educativo y divulgativo permitiendo a la sociedad compostelana de aquella época ser partícipe de un hito histórico y un gran acercamiento a la ciencia. La preparación científica y tecnológica no eran inaccesibles a otros científicos españoles de la época, pero los conocimientos específicos, los elementos materiales y la determinación que se precisaban reunir para llevar adelante el experimento no estaban al alcance de muchos. Pero estamos hablando de un científico que lideró otros eventos de gran trascendencia [2], [3]. Como ya se ha mencionado, se trata de la primera demostración de este tipo que se hace en España, y por ello pensamos que se trata de un hecho que debe ser presentado y valorado en el Simposium de Enseñanza, Divulgación e Historia de la Física dentro de esta Bienal que tiene su sede en la ciudad donde aquel evento se llevó a cabo. La intención de este trabajo es el repaso de los aspectos más importantes del arco voltaico y de las pilas utilizadas para llevarlo a cabo como parte del hecho histórico de su primer uso en iluminación pública en España por Antonio Casares. Esta contribución también tratará de presentar un breve acercamiento a las pilas de combustible como fuente de energía con origen común a las pilas Bunsen, su inventor William Grove, que permiten hoy imaginar un futuro diferente basado en su uso, como ocurrió con aquellas pilas que estuvieron presentes en la efeméride que aquí se presenta. La experiencia original de Antonio Casares El experimento se llevó a cabo la noche del 2 de abril de 1851 [4] en el claustro del edificio central de la Universidad de Santiago de Compostela iluminando la Minerva de la Universidad y la torre de la Iglesia de la Compañía. El montaje consistía en 50 pilas Bunsen en serie como fuentes de energía conectadas a un regulador Deleuil con dos electrodos de grafito encargados de generar el arco voltaico. El experimento diseñado por Casares contaba con 50 pilas tipo Bunsen como fuentes de energía para conseguir la electricidad necesaria para la activación y el mantenimiento del arco voltaico. Estos dispositivos fueron inventados en 1940 por Robert Wilhem Bunsen a partir de una célula previa ideada por el científico galés William Robert Grove. La idea original de Grove consistía en un sistema compuesto por un ánodo de zinc en ácido sulfúrico diluido y un cátodo de platino sumergido en ácido nítrico concentrado y ambos separados por una olla de cerámica porosa. Robert Bunsen modificó el cátodo de platino por una pieza de grafito, material más barato, dando lugar a una reacción con un potencial algo menor. Las reacciones químicas llevadas a cabo por este dispositivo son: 3Zn↔〖3Zn〗^(2+)+6e^- 〖2NO〗_3^-+8H^++6e^-↔2NO+4H_2 O dando lugar a un potencial teórico de 1.72 V, inferior al de las celdas de Grove de 1.9 V. Otro de los elementos importantes del experimento de Casares fue el regulador Deleuil. Este equipo es el encargado de ir posicionando los electrodos de grafito encargados de la formación del arco voltaico tras el desgaste que sufren. En este caso consta de un electrodo fijo y otro montado sobre un sistema móvil regulado por un electroimán en serie con el propio arco. Este sistema también constaba de un espejo parabólico metálico que permitía concentrar la luz y proyectarla sobre un edificio, como se hizo aquella noche. Por último, el elemento más importante para la generación de luz es el arco voltaico, que se obtiene tras la ionización del aire entre ambos electrodos de grafito. A pesar de su uso, el arco eléctrico no es apropiado como sistema de iluminación general porque, independientemente de cuestiones tecnológicas (como el sistema de producción eléctrica) y del coste económico, su brillo era excesivo, resultando insoportable incluso a una distancia importante. También ha de tenerse en cuenta que no fue hasta más de 25 años después cuando se inventó la lámpara incandescente que sería utilizada para la implantación generalizada de la iluminación eléctrica en ciudades a finales del siglo XIX. La experiencia hoy En este trabajo también trataremos de plantear unos cambios en la experiencia de Casares con tecnología más innovadora actual, como son las pilas de combustible y que curiosamente cuentan con un estrecho vínculo común con las baterías utilizadas en 1851, su inventor William Grove. Las pilas de combustible son dispositivos capaces de generar electricidad de manera directa a partir de la energía química contenida en el combustible, tradicionalmente hidrógeno o alcoholes de bajo peso molecular, y el comburente, el oxígeno del aire [5]. A pesar de ser ideadas por Grove solo 4 años después de la pila comentada anteriormente es hoy en día cuando se investigan con mayor interés, suponiendo una gran alternativa energética para el futuro. Estos dispositivos se constituyen de dos electrodos, catódico y anódico, de platino nanoparticulado y una membrana intercambiadora de iones como electrolito. Las reacciones que se llevan a cabo en cada uno de los electrodos son: H_2→〖2H〗^++2e^- 1⁄2 O_2+2e^-+2H^+→H_2 O dando lugar a un potencial teórico de 1.23 V que, como vimos anteriormente es inferior al de las pilas Bunsen utilizadas en la experiencia original. Por ello, es necesario situar más elementos en serie con el fin de obtener similares valores de voltaje. Esta comparativa tratará de dar un enfoque más moderno y actual al evento histórico tratado anteriormente acercándolo al presente, poniendo en valor la experiencia llevada a cabo en su día y presentando los cambios que se podrían realizar con tecnología actual con común origen. Referencias [1] A. Díaz Pazos, Boletín das Ciencias (ENCIGA) 75 (2012) 139. [2] R. Cid, Anales de Química 109 (2013) 27. [3] R. Cid, Revista Española de Física 28 (2014) 59. [4] J. C. Alayo, J. Sánchez Millán, Técnica e ingeniería en España, VI. El Ochocientos. De los lenguajes al patrimonio, IFC - Real Academia de Ingeniería, Zaragoza, 2011. [5] G. G. Scherer, Advances in Polymer Science. Fuel Cells, Springer, Verlag Berlin Heidelberg, 2008.
        Speakers: Dr. Ramón Cid Manzano (Departamento de Didácticas Aplicadas, Facultade de Ciencias da Educación, Universidade de Santiago de Compostela), Dr. Ricardo Escudero Cid (Departamento de Química Física Aplicada, Facultad de Ciencias, Universidad Autónoma de Madrid)
      • 18:30
        Rúbrica para evaluar los informes de laboratorio de Física 15m
        La introducción de una enseñanza por competencias nos lleva a la búsqueda de nuevos instrumentos de evaluación como las rúbricas. En este trabajo, se presenta la encuesta realizada al alumnado de la materia de Física de Ingeniería Química para conocer su opinión sobre la rúbrica diseñada para orientar y evaluar la elaboración del informe de prácticas. Los resultados de esta encuesta nos muestran que la rúbrica es fácil de entender, contiene los elementos principales para el desarrollo del informe y sirve de orientación para la realización del informe de laboratorio.
        Speaker: Mrs. Encina Calvo Iglesias (USC)
      • 18:45
        Scary Physics: la Física detrás del terror 15m
        Con el principal objetivo de mostrar la física de una forma alternativa a la tradicional, la asociación sin ánimo de lucro Physics League de Valladolid ha creado el show divulgativo “Scary Physics”. Dicho espectáculo está dirigido al público en general y presenta distintos fenómenos físicos en el guión de una obra teatral aterradora. Para acercar todavía más los distintos sucesos al público, se han utilizado villanos y distintos personajes de películas de terror para ambientar el espectáculo.
        Speaker: Mrs. Veronica Gonzalez Fernandez (Universidad de Valladolid)
      • 19:00
        HITOS Y DIDACTICA DE LA TERMODINÁMICA EN EEEMM 15m
        Aunque en los currículos actuales de Química de las EEMM la docencia de conceptos tan abstractos como la entalpía, la entropía y la energía libre, se proponen ya en 1º de Bachillerato (antes en 2º) como meros algoritmos aplicados a casos concretos de predicción de espontaneidad de reacciones químicas, entalpía de procesos, etc.. el hecho es que este tema sigue siendo el de peor comprensión de todo el temario para los chicos y el más incómodo de impartir para los profesores críticos. Creo que procede una revisión cualitativa de estos tópicos desde una perspectiva histórica que puede añadir rigor, claridad, amenidad, y una dimensión tecnológica al tema. Se comentan al final algunos recursos para la didáctica del primer principio.
        Speaker: Mr. francisco sotres (grupo de didactica e historia de la fisica y quimica)
    • 15:15 19:00
      Molecular Physics at the Edge II Aula Matemáticas (Facultad de Química (USC))

      Aula Matemáticas

      Facultad de Química (USC)

      • 15:15
        Experimental characterization of the basic intermolecular interaction components 30m
        The target of the present work is the detailed characterization of the most relevant components of the intermolecular interaction, which control the molecular dynamics under a variety of conditions. To this purpose, molecular beam experiments have been performed under conditions proper to isolate quantum effects in the single collision events, which probe in detail the projectile-target interaction. Particular attention is addressed to range, strength and anisotropy of non-covalent interaction components, due to the balance of size (or Pauli) repulsion with dispersion and induction attraction, to which must be added electrostatic contributions, and of other components of covalent (chemical) nature, mostly affected by charge (electron) transfer effects. The analysis of several experimental findings has been important to develop suitable analytical representations of the potential energy surfaces (PESs), tested and improved by exploiting also the comparison with results of ab initio calculations, useful to provide an internally consistent description of the intermolecular interaction both in the most and less stable configurations of the interacting system. The proper formulation of the PESs is crucial not only to describe the dynamics of elementary processes occurring in interstellar medium and in planetary atmospheres, but also to control equilibrium a non-equilibrium phenomena of applied interest, as those occurring in combustion, flames and plasmas. Acknowledgment The financial support of this research is from the “Fondazione Cassa di Risparmio di Perugia” (Contract No. 2015.0331.021) and from the “Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia”
        Speaker: Prof. Fernando Pirani (Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia)
      • 15:45
        Ultrafast broadband transient absorption spectroscopy of a single molecule 20m
        We present the first ultrafast transient absorption of a single molecule. Specifically, we trace the femtosecond evolution of excited electronic state spectra of single molecules over hundreds of nanometers of bandwidth at room temperature. The non-linear ultrafast response of the single molecule is probed using a broadband laser in an effective 3-pulse scheme with fluorescence detection. A first excitation pulse is followed by a phase-locked de-excitation pulse-pair, providing spectral encoding while preserving 25 fs temporal resolution. This experimental realization of true single molecule transient absorption spectroscopy demonstrates that two-dimensional electronic spectroscopy of single molecules is experimentally in reach.
        Speaker: Prof. Niek F. van Hulst (ICFO - the Institute of Photonic Sciences)
      • 16:05
        The quest towards supramolecular networks from first principles 20m
        How far into molecular complexity can we get from first principles? Can we predict specific recognitions between molecules from the computation of the relevant conformations and interactions? Is it then possible to forsee how assemblies of molecules spontaneously conform functional nanostructures and materials? Will we ever understand the behaviour of living organisms from the investigation of their molecular building blocks? Should we even dare? These are challenging but central questions in the scientific activity of chemical physicist. A modest illustration of this topic can be obtained from an overview of the incursions of our group into molecular recognition and supramolecular aggregation over the last decade.
        Speaker: Dr. Bruno Martínez Haya (Universidad Pablo de Olavide)
      • 16:25
        Acid dissociation in microsolvated environments 20m
        The long-standing and fundamental question regarding the minimum number of water molecules required to dissociate an acid molecule in an aqueous microsolvation environment still remains open. For HCl interacting with water molecules - one added after the other - there is convincing evidence that an ion pair, and thus the dissociated acid molecule, can be stabilized using a minimum number of only four water molecules (see Fig. 1) [1,2]. However, this number has been questioned both on the experimental [3–6] and the theoretical sides [7]. In this respect, an experiment appeared recently in the literature [8] which suggested a new approach. In this experiment the dipole moment of HCl•(H2O)n clusters was measured as a function of the number of water molecules (see Fig. 2). The key result of those measurements was a noticeable rise of the total dipole moment of these clusters when n=6. A tempting explanation was to assign this sudden rise in the dipole moment to the dissociation of the HCl molecule. In this work, ab initio path integral calculations were performed in order to try to disentangle the controversy of whether it is 4 or 6 water molecules the minimum required to dissociate the chloridric acid. Our results show that measuring the dipole moment of HCl•(H2O)n clusters does not give any information about the dissociative state of the HCl molecule. In addition, a detailed analysis of thermal and quantum effects provides a much clearer picture of the acid dissociation process in microsolvated environments. The Cluster of Excellence “RESOLV” (EXC 1069) funded by the Deutsche Forschungsgemeinschaft (DFG) is gratefully acknowledged along with computer time support from HPC-RESOLV, HPC@ZEMOS, BOVILAB@RUB and RV-NRW. References [1] A. Gutberlet, G. Schwaab, Ö. Birer, M. Masia, A. Kaczmarek, H. Forbert, M. Havenith, D. Marx, Science 324 (2009) 1545. [2] H. Forbert, M. Masia, A. Kaczmarek-Kedziera, N. N. Nair, D. Marx, J. Am. Chem. Soc. 133, (2011) 4062. [3] D. Skvortsov, S. J. Lee, M. Y. Choi, and A. F. Vilesov, J. Phys. Chem. A 113, (2009) 7360 . [4] S. D. Flynn, D. Skvortsov, A. M. Morrison, T. Liang, M. Y. Choi, G. E. Douberly, A. F. Vilesov, J. Phys. Chem. Lett. 1 (2010) 2233. [5] A. M. Morrison, S. D. Flynn, T. Liang, G. E. Douberly, J. Phys. Chem. A 114 (2010) 8090. [6] M. Letzner, S. Gruen, D. Habig, K. Hanke, T. Endres, P. Nieto, G. Schwaab, L. Walewski, M. Wollenhaupt, H. Forbert, D. Marx, M. Havenith, J. Chem. Phys. 139 (2013) 154304. [7] A. Vargas-Caamal, J. L. Cabellos, F. Ortiz-Chi, H. S. Rzepa, A. Restrepo, G. Merino, Chem. Eur. J. 22 (2016) 2812. [8] N. Guggemos, P. Slavíček, V. V. Kresin, Phys. Rev. Lett. 114 (2015) 043401.
        Speaker: Dr. Ricardo Pérez de Tudela (Lehrstuhl für Theoretische Chemie, NC 03/52, Ruhr-Universität Bochum, 44780 Bochum, Germany)
      • 16:45
        Hybrid Organic-Inorganic Halide Perovskites for Photovoltaics and Lasing Applications: Insights from First Principles Calculations 20m
        see attached file
        Speaker: Dr. Giacomo Giorgi (Department of Civil and Environmental Engineering (DICA), The University of Perugia, Perugia, Italy)
      • 17:05
        Coffee break 25m
      • 17:30
        Revealing the low-energy landscape of clusters: from the solvation of ions to the self-assembling of colloidal particles 30m
        Introduction Knowledge about the structure that different types of matter may acquire is fundamental to understand several properties emerging around in Nature and to build up new materials. Such structural organization can be observed at different scales, ranging from aggregates of atoms in the gas-phase to colloids in condensed-matter physics. From the theoretical view point, one has to model the interactions among the particles of the system (e.g., atoms or molecules) and, then, apply optimization techniques. In general, this is a very difficult task that requires the application of state-of-the-art optimization methods. Over the past decade or so, we have developed evolutionary algorithms (EAs) that has been able to discover putative global minima for various cluster systems, including atomic [1-3], molecular [4] and colloidal [5,6] clusters. In this talk, we will present the main ingredients of our EA and its application to the solvation of ions [7,8] as well as to the study of self-assembling phenomena in colloidal systems [6,9,10]. In particular, we will focus on the study of alkali-ions solvation (Figure 1) and the formation of aggregates of charged colloidal particles (Figure 2). The analysis of the energetics and structure of the clusters relies on the features of the potential functions employed for modeling the interactions among the particles. Acknowledgments We acknowledge the support from the Coimbra Chemistry Center (CQC), which is financed by the Portuguese “Fundação para a Ciência e a Tecnologia” (FCT) through the Project No 007630 UID/QUI/00313/2013, co-funded by COMPETE2020-UE. We also acknowledge the FCT/CAPES bilateral Project (Ref: 2984/DRI and 88887.125439/2016-00/CAPES). References [1] F.B. Pereira, J.M.C. Marques, T. Leitão, J. Tavares, “Designing efficient evolutionary algorithms for cluster optimization: a study on locality”, in: P. Siarry, Z. Michalewicz (Eds.), Advances in Metaheuristics for Hard Optimization (Springer Natural Computing Series), Springer, Berlin, 2008, pp. 223-250. [2] F.B. Pereira, J.M.C. Marques, Evol. Intel. 2 (2009) 121. [3] J.M.C. Marques, F.B. Pereira, Chem. Phys. Lett. 485 (2010) 211. [4] J.L. Llanio-Trujillo, J.M.C. Marques, F.B. Pereira, J. Phys. Chem. A 115 (2011) 2130. [5] J.M.C. Marques, F.B. Pereira, J. Mol. Liq. 210 (2015) 51. [6] S.M.A. Cruz, J.M.C. Marques, F.B. Pereira, J. Chem. Phys. 145 (2016) 154109. [7] J.M.C. Marques, F.B. Pereira, J.L. Llanio-Trujillo, P.E. Abreu, M. Albertí, A. Aguilar, F. Pirani, M. Bartolomei, Phil. Trans. R. Soc. A 375 (2017) 20160198. [8] F.V. Prudente, J.M.C. Marques, F.B. Pereira, in preparation. [9] S.M.A. Cruz, J.M.C. Marques, J. Phys. Chem. B 120 (2016) 3455. [10] S.M.A. Cruz, J.M.C. Marques, Comput. Theor. Chem. 1107 (2017) 82.
        Speaker: Prof. Jorge Marques (Department of Chemistry, University of Coimbra)
      • 18:00
        Coarse-graining polycyclic aromatic hydrocarbon clusters 20m
        In this talk we present a coarse-grained model based on the Paramonov-Yaliraki (PY) potential [1] for modeling interacting polycyclic aromatic hydrocarbon (PAH) molecules [2]. This model is parameterized using all-atom reference data to study coronene (C24H12), circumcoronene (C54H18) and their aggregates. We show the ability of the coarse-grained approach to reproduce the global minima predicted by the all-atom potential for clusters containing up to 20 molecules. One-dimensional columnar motifs are found to be most favourable in small clusters with mixed stacks in larger clusters. Dynamical and thermodynamical properties of the coronene octamer are discussed in the energy landscapes framework [3]. From a connected database of stationary points of the potential energy surface and using the harmonic normal mode approximation, we show the potential and free energy landscapes and relevant rearrangement pathways between competing motifs, as determined using discrete path sampling [4], which exhibit highly cooperative motion [5].
        Speaker: Dr. Javier Hernandez-Rojas (Departamento de Física, Universidad de La Laguna)
      • 18:20
        Experimental and simulation studies of the stepped adsorption of gases on silicalite-2 20m
        Zeolites are materials with a well-defined microporous geometry which make them attractive for many industrial applications, for example, in catalysis or in the separation of mixtures. Understanding their adsorption behaviour is therefore an issue of major relevance from a practical point of view, but also from a fundamental one, as it is common that the properties of the adsorbed fluid are different from those in the bulk. One intriguing finding in this context is the observation that the adsorption isotherm of some simple gases (such as argon) on silicalite-1 exhibits a sub-step at intermediate loadings whereas others (such as methane) do not. Even though considerable experimental and theoretical efforts have been made, the origin of this sub-step is not clear. Some authors claim that this behaviour is a result of a fluid-like to solid-like transition of the adsorbed fluid, whereas others attribute it to a zeolite structural change. With the aim of providing more information that may aid to understand the appearance of sub-steps in the adsorption of some gases in silicalite-1, we have carried out a comprehensive experimental and simulation study of the adsorption of argon and toluene on the structurally similar zeolite silicalite-2. Both zeolites exhibit a similar structure consisting on a three-dimensional network of fairly narrow cylindrical channels with diameters in the range of 5.0 to 5.6 Å. The essential difference lies in the fact that silicalite-1 consists of an array of parallel cylindrical pores intersected by sinusoidal channels, whereas in silicalite-2 all the pores are linear (see Figure 1). First we performed volumetric experiments that confirm that the adsorption of argon and toluene on silicalite-2 also exhibits a sub-step at half loading (see Figure 2), suggesting that this behaviour does not depend on the specific structural details of the pores. Subsequently, the microscopic origin of this sub-step was investigated by means of molecular simulations. However, the agreement between the experimental and simulated adsorption isotherm was only qualitative, evidencing deficiencies of the models used to describe the interactions between the different components in the system. Thus the structure of the adsorbate/adsorbent system was further investigated by performing powder diffraction experiments at three different loads: empty, at half-load (before the sub-step) and at high load (after the sub-step). These data were used as input of N-Reverse Monte Carlo simulations to obtain atomic structural models compatible with the experimental diffractograms. In both instances, namely adsorption of argon and toluene, a good fit of the experimental data was only obtained when incorporating the zeolite flexibility, which shows that the structure of the zeolite can change at high loads or when the size of the adsorbed molecules is comparable to that of the pores. In the case of argon, after the sub-step, a considerable order of the fluid also builds up, suggesting that the sub-step might be attributed to a fluid structural change facilitated by a slight deformation of the zeolite. Interestingly, the structural models obtained from Monte Carlo and N-Reverse Monte Carlo simulations are significantly different, even at half loading. We ascribe these discrepancies to deficiencies in the adsorbent-adsorbate interatomic potential.
        Speaker: Dr. Gonzalez Eva (CSIC)
      • 18:40
        Computational study of mixtures of ILs and alcohols under nanoconfinement conditions 20m
        Mixtures of 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF4] ionic liquid with molecular amphiphilic solvents, methanol and ethanol under nanoconfinement between neutral and charged graphene walls are studied in this work by means of molecular dynamics simulations. The adsorption of alcohol molecules in the walls as well as their distribution in the directions normal and parallel to the interface are studied. The results of these simulations are compared with results of the pure IL and its mixtures with water, which were previously reported in ref. [1]. All the results suggest that alcohols distribute quite uniformly throughout the box, being almost totally depleted from graphene walls. The distribution of ions of the first and second layers closest to the electrodes in the direction parallel to these are also studied by means of bidimensional density maps, showing a clear structural transition from a striped pattern to an hexagonal one with the concentration of cosolvent and also when the size of the cosolvent molecules increases. These transitions seem to be highly sensitive to the presence of cosolvent molecules in the ionic layers closest to the electrodes. It was also corroborated that the bidimensional ionic structures persist in the second ionic layer close to the graphene walls. This persistence of the bidimensional ionic structure combined with the electric double layer (see refs. [2-5]) strongly conditions the three dimensional ionic structure near charged interfaces in these dense ionic systems. Moreover, recent studies have shown that this bidimensional structures appear in ILs in other circumstances, like mixtures with salts, mixtures with other cosolvents solvents like water or when the graphene walls have vacancy defects (see ref. [6]). In this work we report the formation of these structures when the molecular size of the solvent changes. References [1] B. Docampo-Álvarez, V. Gómez-González, H. Montes-Campos, J. M. Otero-Mato, T. Méndez-Morales, O. Cabeza, & L. M. Varela (2016). J. Phys. Cond. Mat., 28(46), 464001. [2] A. A. Kornyshev, (2007). J. Phys. Chem. B, 111(20), 5545-5557. [3] M. V. Fedorov & A. A. Kornyshev, (2008). J. Phys. Chem. B, 112(38), 11868-11872. [4] M. V. Fedorov, N. Georgi & A. A. Kornyshev, (2010). Electrochem. Commun., 12(2), 296-299. [5] M. Z. Bazant, B. D. Storey & A. A. Kornyshev, (2011). Phys. Rev. Lett., 106(4), 046102(1)-046102(4). [6] H. Montes-Campos, J. M. Otero-Mato, T. Méndez-Morales, O. Cabeza, L. J. Gallego, A. Ciach, R. M. Lynden-Bell & L. M. Varela, (2017). Submitted for publication.
        Speaker: Mr. José Manuel Otero Mato (Universidad de Santiago de Compostela)
    • 15:15 19:05
      Quantum Materials and Technologies (GEFES) II Aula Química Inorgánica (Facultad de Química (USC))

      Aula Química Inorgánica

      Facultad de Química (USC)

      • 15:15
        Andreev levels in hybrid superconductor-semiconductor nanowire quantum dots: Energy scaling and spin texture 30m
        The interaction of a magnetic impurity and a superconductor yields localized states known as Andreev levels or Yu-Shiba-Rusinov (YSR) states. Recently, there has been a growing interest in this type of system, in a large part, due to theoretical work that suggests that Andreev levels are precursors of Majorana zero modes. Accordingly, it has been proposed that chains of such impurities could be engineered, under appropriate conditions, into a topological superconductor [1-9]. A semiconductor quantum dot coupled to a superconductor constitutes a versatile platform to investigate, in a controllable and quantitative manner, the physics of the corresponding single-impurity limit. Here, we have employed single quantum dots defined in an InAs nanowire, coupled strongly to a superconductor and weakly to a normal metal probe, to study the Andreev levels by tunneling spectroscopy. First, we exploit the ability to tune the hybridization of the quantum dot and the superconductor to quantitatively investigate the energy scaling of Andreev levels. We demonstrate that the energy of such sub-gap excitations scales with the ratio of the Kondo temperature and the superconducting gap. We further leverage the electrical control over device parameters to obtain an experimental phase diagram of the possible ground states: a spin singlet or a magnetic doublet. Our experimental results show remarkable quantitative agreement with numerical renormalization group calculations [10]. In parallel, we have studied the spin texture of the Andreev levels in the presence of an external magnetic field. We demonstrate that the Zeeman effect results in a splitting of the sub-gap states only when the ground state is a spin singlet. In this case, the applied magnetic field can also lead to a quantum phase transition to a spin-polarized ground state [11]. The herein demonstrated electrical tuning of Andreev levels as well as their spin-polarization could be harnessed to pursue proposals of realizing a topological superconductor using quantum dot arrays [7-9]. [1] S. Nadj-Perge et al., Phys. Rev. B 88, 020407(R) (2013). [2] K. Klinovaja et al., Phys. Rev. Lett. 111, 186805 (2013). [3] M. M. Vazifeh and M. Franz, Phys. Rev. Lett. 111, 206802 (2013). [4] B. Braunecker and P. Simon, Phys. Rev. Lett. 111, 147202 (2013). [5] F. Pientka et al., Phys. Rev. B 88, 155420 (2013). [6] S. Nadj-Perge et al., Science 346, 602 (2014) [7] J. D. Sau and S. Das Sarma, Nat. Commun. 3, 964 (2012). [8] M. Leijnse and K. Flensberg, Phys. Rev. B 86, 134528 (2012) [9] I. C. Fulga et al., New J. Phys. 15, 045020 (2013). [10] Lee et al., to appear in Phys. Rev. B – Rapid Commun. [11] Lee et al., Nat. Nanotechnol. 9, 79 (2014).
        Speaker: Dr. Eduardo Jian Hua Lee (Instituto de Fisica de la Materia Condensada - Universidad Autonoma de Madrid)
      • 15:45
        Mapping the orbital structure of Shiba states in a superconductor 20m
        Magnetic impurities inside a superconductor locally distorts superconductivity. They scatter Cooper pairs as a potential with broken time-reversal symmetry, what leads to localized bound states (usually refered as Shiba states) with subgap excitation energies. These states, first predicted by Yu, Shiba, and Rusinov [1], are identified in scanning tunneling spectra as pairs of intra-gap resonances symmetrically positioned around zero-bias. Most conventional approaches to study Shiba states treat magnetic impurities as point scatterers with an isotropic exchange interaction, while the complex internal structure of magnetic impurities is usually neglected. Due to the orbital character of the scattering channels of the impurities, it is expected that Shiba multiplets reflect the occupation level of the atomic shell, what would render them as the ideal probe for identifying the magnetic ground state of a single impurity in a superconductor. In this presentation, I will show high-resolution scanning tunneling spectroscopy measurements and Density Functional Theory simulations, which provide evidence that that the number and shape of Shiba states are correlated to the spin-polarized atomic orbitals of the impurity, hybridized with the superconducting host. We investigated Cr impurities on Pb(111) [2] and spatially map the five Shiba excitations found inside the superconducting gap, resolving both their particle and hole components. While the maps of particle components resemble the d orbitals of embedded Cr atoms, the hole components differ strongly from them. The orbital fingerprints of Shiba states thus unveil the magnetic ground state of the impurity, and identify scattering channels and interactions, all valuable tools for designing atomic-scale superconducting devices.
        Speaker: Prof. Nacho Pascual (Ikerbasque Research Professor ,CIC nanogune)
      • 16:05
        Zero-energy pinning from interactions in Majorana nanowires 20m
        Majorana zero modes at the boundaries of topological superconductors are charge-neutral, an equal superposition of electrons and holes. This ideal situation is, however, hard to achieve in physical implementations, such as proximitised semiconducting nanowires of realistic length. In such systems Majorana overlaps are unavoidable and lead to their hybridisation into charged Bogoliubov quasiparticles of finite energy which, unlike true zero modes, are affected by electronic interactions. We here demonstrate that these interactions, particularly with bound charges in the dielectric surroundings, drastically change the non-interacting paradigm. Remarkably, interactions may completely suppress Majorana hybridisation around parity crossings, where the total charge in the nanowire changes. This effect, dubbed zero-energy pinning, stabilises Majoranas back to zero energy and charge, and leads to electronically incompressible parameter regions wherein Majoranas remain insensitive to local perturbations, despite their overlap.
        Speaker: Dr. Pablo San-Jose (ICMM-CSIC)
      • 16:25
        Measuring Majorana non-locality and spin structure with a quantum dot 20m
        Robust zero bias transport anomalies in semiconducting nanowires with proximity-induced superconductivity have been convincingly demonstrated in various experiments. While these are compatible with the existence of Majorana zero modes at the ends of the nanowire, a direct proof of their non-locality and topological protection is now needed. Here we show that a quantum dot at the end of the nanowire may be used as a powerful spectroscopic tool to quantify the degree of Majorana non-locality through a local transport measurement. Moreover, the spin polarization of dot sub-gap states at singlet-doublet transitions in the Coulomb blockade regime allows the dot to directly probe the spin structure of the Majorana wavefunction, and indirectly measure the spin-orbit coupling of the nanowire.
        Speaker: Dr. Elsa Prada (Universidad Autónoma de Madrid)
      • 16:45
        Coffee Break and Posters 1h
      • 17:45
        Graphene based nuclear spin quantum bits 20m
        In this work, we study the possibility of hydrogenated graphene based Qubits. The chemisorption of hydrogen in graphene provides a nuclear spin 1/2 as well as the localization of an electron in the vicinity of the adatom, very much like in the Qubits based on P donors in Si[1-4]. The possibility to control with atomic precision the chemisorption of hydrogen[5], along with the high tunability of the electronic properties of graphene (and graphene nano-structures)[6], offers a great tool to control the interactions in the system allowing to perform single and two-qubit operations. We use a 4 orbital tight-binding model in the Slater-Koster approximation, validated with DFT calculations, to explore the tunability of the interactions and the feasibility of these ideas. [1] B. E. Kane, Nature 393, 133-137 (1998) [2] A. Morello, et al Nature 467, 687–691 (2010) [3] M. Veldhorst, et al, Nature Nanotechnology 9, 981–985 (2014) [4] J. P. Dehollain, et al, Nature Nanotechnology 9, 986–991 (2014) [5] H. González-Herrero, et al, Science 352, 437 (2016) [6] Y. Zhang, et al, Nature, 459, 820–823 (2009)
        Speaker: Mr. Noel Garcia (International Iberian Nanotechnology Laboratory)
      • 18:05
        Manipulability, coherence and entanglement of acceptor qubits in Si and Ge 20m
        The search for electric field manipulable spin qubits has focused the attention in the recent years to high spin-orbit systems. These systems mix the spin with orbital degrees of freedom. As the orbital wavefunction is sensitive to electric fields, this mixing allows the possibility of manipulating spins entirely by electric means. The large spin-orbit coupling in the valence band of group IV semiconductors provides then with an electric field knob for hole based spin-qubit manipulation. Si and Ge are also known for their extraordinary coherence properties, making them two of the most promising candidates to host spin-qubits. In this work we consider acceptor impurities placed in these hosts. These acceptors behave as spin-3/2 particles with remarkable properties that can be tuned through both electric and magnetic fields. We find that the spin manipulation of holes bound to acceptors in engineered SiGe quantum wells depends very strongly on the electric field applied and on the heterostructure parameters. The g-factor is enhanced by the Ge content and can be tuned by shifting the hole wave-function between the heterostructure constituent layers. The lack of inversion symmetry induced both by the quantum well and the electric fields together with the g-factor tunability allows the possibility of different qubit manipulation methods such as electron spin resonance, electric dipole spin resonance and g-tensor modulation resonance. Rabi frequencies up to hundreds of MHz can be achieved with heavy-hole qubits, and of the order of GHz with light-hole qubits. We also find that by carefully choosing the parameters of the system such as the in-plane magnetic field and the applied vertical electric field it is possible to tune the entanglement and coherence properties of the system.
        Speaker: Mr. José Carlos Abadillo-Uriel (Instituto de Ciencia de Materiales de Madrid, CSIC)
      • 18:25
        Coupling small spin ensembles to superconducting on-chip resonators: towards a hybrid architecture for quantum information 20m
        The field of cavity quantum electrodynamics (QED) studies the interaction of photons in resonant cavities with either natural or “artificial” atoms, such as quantum dots and superconducting qubits, having a nonlinear and discrete energy level spectrum [1]. For applications in spectroscopy and especially quantum information processing, a major goal is to maximize the coupling strength g1 of the atom to either electric or magnetic cavity fields, making it larger than the decoherence rates of both the cavity and the atom (strong coupling regime). Attaining this regime for individual spin qubits would open the possibility of developing an all-magnetic quantum processor [2]. This goal remains, however, very challenging because the interaction of each spin with the photon’s magnetic field is much weaker than the typical decoherence rates of the resonator and of most magnetic qubits. For this reason, strong coupling has been observed only in the case of macroscopic spin ensembles, containing N > 10^12 spins, for which the effective collective coupling gN is enhanced by a factor N^(1/2) with respect to that of a single spin [3,4]. We have recently shown that the microwave magnetic field of a coplanar superconducting resonator can be enhanced locally via the fabrication of nanoscopic constrictions at its central line [5]. In this communication, we report the results of experiments performed on small spin ensembles directly deposited onto such constrictions. 1.5 GHz superconducting resonators were fabricated by optical lithography on Nb layers grown onto crystalline sapphire substrates. A typical design is shown in Fig. 1A. The width w of the central line can be reduced from the original 14 microns down to less than 50 nm by using a focused beam of Ga+ ions, without appreciably altering the resonator characteristics (Figs. 1B and 1C) [5]. Experiments were also performed using a w = 400 microns wide central line resonator. The magnetic samples consist of ensembles of DPPH free radicals, each having a spin s = 1/2 with a fully isotropic gyromagnetic factor g = 2 and a negligibly small inhomogeneous broadening.6 Molecules were deposited onto the devices from a saturated solution in DMSO. For large ensembles on standard resonators, the deposition was made using a micropipette and the size of the spin ensemble varied by controlling the droplet volume. Smaller spin ensembles were deposited using dip-pen nanolithography.7 The tip of an atomic force microscope (AFM) is used to write small dots (between 5 and 60 microns wide) with a very high spatial resolution. The number of spins N lying inside the area of the constriction was accurately determined from Scanning Electron Microscopy and AFM experiments (Fig 1D). The transmission S21 of microwave radiation trough the resonators was measured at T = 4.2 K as a function of magnetic field and frequency omega. The maximum transmission, near the ground mode at omega/2pi = 1.5 GHz, and the effective Q factor decrease sharply when the field brings the spins into resonance with the circuit. From these experiments, the collective coupling constant has been determined for samples with N varying between 10^8 and 10^16 spins. The results (Fig. 1 E) show that gN is proportional to N^(1/2) both for the original resonators and for the constrictions. However, the average coupling to each spin g1 = gN/N^(1/2), is enhanced by more than two orders of magnitude (from 0.25 Hz up to 50 Hz) in the latter case. As a result, magnetic ensembles, e.g. a 30 microns drop, that are completely undetectable with a conventional resonator become visible when they are deposited near a superconducting nano-bridge. Furthermore, the dependence of g1 on the width of the central line agrees quantitatively with theoretical predictions (Fig. 1 F) [8]. These results show that the coupling of spin qubits to quantum superconducting circuits can be enhanced via a combination of top-down and bottom up nanolithography techniques. In the present experiments, the spin-photon coupling remains in the weak coupling regime because DPPH shows decoherence rates 1/T2 > 12 MHz. The strong coupling regime might, however, be attained for especially designed molecular spin qubits that can show 1/T2 values as small as 1 kHz [9]. Furthermore, reaching this limit for individual spins, a pre-requisite for the development of a magnetic quantum processor, will then also be feasible provided that nanofabrication techniques are pushed down to w < 10 nm. References [1] R. J. Schoelkopf and S. M. Girvin, Nature 451 (2008) 669 [2] M. D. Jenkins, D. Zueco, O. Roubeau, G. Aromí, J. Majer and F. Luis, Dalton Trans. 45 (2016) 16682. [3] D. I. Schuster et al, Phys. Rev. Lett. 105 (2010) 140501 [4] R. Amsüss et al, Phys. Rev. Lett. 107 (2011) 060502 [5] M. D. Jenkins et al, Applied Physics Letters 105 (2014) 162601 [6] N. D. Yordanov, Appl. Magn. Res. 10 (1996) 339 [7] M. J. Martínez-Pérez, E. Bellido, R. de Miguel, J. Sesé, A. Lostao, C. Gómez-Moreno, D. Drung, T. Schurig, D. Ruiz-Molina, and F. Luis, Applied Physics Letters 99 (2011) 032504 [8] M. D. Jenkins, T. Hümmer, M. J. Martínez-Pérez, J. J. García-Ripoll, D. Zueco and F. Luis, NJP 15 (2013) 095007 [9] J. M. Zadrozny, J. Niklas, O. G. Poluektov and D. E. Freedman, ACS Cent. Sci. 1 (2015) 488
        Speaker: Dr. Fernando Luis (Instituto de Ciencia de Materiales de Aragón (ICMA), CSIC-Universidad de Zaragoza)
    • 15:15 18:45
      Quantum and Non-linear Optics Aula Química General (Facultad de Química (USC))

      Aula Química General

      Facultad de Química (USC)

      • 15:15
        Domain Statistics Analysis of Disordered Structures via Second Harmonic Generation 20m
        We show a method to experimentally characterize the any 2D random distribution of ferroelectric domains in a nonlinear crystal such as SBN, which is difficult to observe by other methods. It is based on second harmonic diffraction of light pulses and it allows us to determine the domain size distribution. Comparison with simulation results shows good agreement. It has also been used to characterize more complicated domain distributions.
        Speaker: Prof. Ramon Vilaseca (Universitat Politecnica de Catalunya (UPC))
      • 15:35
        Generación de haces de luz vectoriales mediante láminas-Q 20m
        Los haces de luz vectoriales, con un patrón de polarización no uniforme en su sección, están recibiendo mucha atención debido a sus interesantes aplicaciones. Estos haces pueden generarse mediante las denominadas láminas-q, retardadores lineales cuyo eje óptico rota una fracción q del ángulo azimutal. En esta comunicación revisamos los trabajos recientes de nuestro grupo en la generación de haces vectoriales mediante láminas-q. Presentamos resultados obtenidos con tres tipos de dispositivos. En primer lugar, un prototipo sementado y sintonizable, de cristal líquido. En segundo lugar, láminas q comerciales, no sintonizables, por lo que debe especificarse la longitud de onda de operación y no sementadas. Finalmente, hemos diseñado un sistema óptico que implementa láminas-q arbitrarias en un modulador espacial de luz (SLM) de cristal líquido. Ello permite generar nuevos diseños con valores arbitrarios de q (negativos, fraccionales). Además, permite codificar láminas-q combinadas simultáneamente con otros elementos ópticos, y generar así haces vectoriales exóticos.
        Speaker: Prof. María del Mar Sánchez López (Universidad Miguel Hernández)
      • 15:55
        Stable Bessel Vortex Beams Sustained By Multiphoton Absorption In Self-focusing Kerr Media 20m
        Bessel vortex beams (BVBs) are vorticity-carrying nonlinear Bessel modes, propagation-invariant solutions of the nonlinear Schödinger equation with Kerr and multiphoton absorption (MPA) nonlinearities. As for the fundamental nonlinear Bessel beam case, their stationarity is supported by a power reservoir mechanism, which arises from its weak localization. In this work it is demonstrated how the MPA effect provides BVBs of simple and multiple topological charges with complete stability against both azimuthal breakup and collapse. A linearized stability analysis for small perturbations is used to vaticinate the stabilizing properties, and direct numerical simulations to verify the results. Furthermore, it is described how the model here proposed allows a common explanation to the three dynamical regimes previously observed in axicon-generated vortex beams propagating in nonlinear media: tubular, rotatory or specklelike filament regimes.
        Speaker: Mr. Márcio Bruno Da Silva Matos Carvalho (Universidad Politécnica de Madrid)
      • 16:15
        Extreme nonlinear response in graphene 20m
        High-order harmonic generation (HHG) is a remarkable process resulting from the interaction of physical systems with intense electromagnetic radiation. The generation of high-order harmonics is well-established in atomic and molecular gases. However, much progress have been done towards HHG in solids since the first experimental observation. HHG from solids has burgeoned a great interest, mainly motivated by the quadratic scaling of the harmonic conversion efficiency with the density of the target, as a result of the coherent nature of the process. While semiconductors materials have been well studied, it is not the case for two-dimensional materials as graphene. In this work we present a theoretical approach to describe the induced dynamics responsible for HHG in graphene. We predict the possibility to produce HHG with few-cycle mid-IR laser pulses.
        Speaker: Dr. Antonio Picón (Universidad de Salamanca)
      • 16:35
        Photonic analogs of wave-like dark matter 20m
        We point out formal connections between the astrophysical dynamics of dark matter and the propagation of laser beams in thermooptical media. This paves the way for the design of experiments with dark matter analogs and for cross-fertilization between these two fields.
        Speaker: Dr. Angel Paredes Galan (Universidade de Vigo)
      • 16:55
        Coffee break 30m
      • 17:25
        Mode-division (de)multiplexing using adiabatic passage and supersymmetric waveguides 20m
        Integrated optical devices exhibiting both high fidelity and high speed transmission are expected to foster novel communication platforms paving the way for scalable photonic quantum technologies. Moreover, the emerging technology of Space-Division Multiplexing [1] has recently attracted a lot of attention due to the increasing demand of high-capacity optical transmissions and the proximity of the capacity crunch, being Mode-Division Multiplexing (MDM) one of the solutions proposed to take profit of the spatial degrees of freedom working with multimode channels. In this context, integrated MDM devices are being developed using many different approaches including Supersymmetric (SUSY) optical devices [2] which are one of the most promising alternatives to standard spatial multiplexing devices offering global phase-matching and efficient mode conversion in an integrated and scalable way. However, the main drawback of SUSY optical devices is their lack of robustness against variations of parameter values such as light's wavelength and their sensitiveness to experimental imperfections. This can be solved making use of Spatial Adiabatic Passage (SAP) techniques which have been proposed and experimentally reported as a high-efficient and robust method to transfer a light beam between the outermost waveguides in a system of three identical evanescently-coupled waveguides [3]. We propose to combine SUSY and SAP techniques to design an efficient and robust device which can be used for multiplexing/demultiplexing spatial modes, to manipulate and study the modal content of an input field distribution or to filter signals and remove non-desired modes [4]. We demonstrate that a system of three coupled waveguides, with two identical step-index external waveguides and a supersymmetric central one, engineered along the propagation direction to optimize SAP for the first excited spatial mode of the step-index waveguides, can be used to demultiplex a superposition of the two lowest (m=0,1) transverse electric TEm spatial modes. Thus, we obtain a great improvement in terms of robustness and efficiency with output fidelities F>0.90 for a broad range of geometrical parameter values and light's wavelengths, reaching F=0.99 for optimized values at the telecom wavelength λ=1.55 µm. Although we have designed the device to operate at telecom wavelengths, it can be optimized to work at different wavelengths and moreover, due to its high efficiency for a broad wavelength range, it may be used for mode filtering of light pulses and it is fully compatible with wavelength division multiplexing. As a proof of principle, we have focused on the simplest possible case for which only two TE spatial modes can propagate through the step-indexplanar waveguides but this configuration can be generalized to a higher number of TE modes, to transverse magnetic modes or even to orbital angular momentum modes in multimode optical fibers. In addition, the device can be engineered to separate different modes by applying SUSY reiteratively and more complex devices can be constructed in order to demultiplex N spatial modes in an efficient and robust way by coupling in series different devices. Finally, the high obtained fidelities open promising perspectives in the field of quantum integrated photonics to, for instance, prepare and manipulate quantum states with minimal errors or by taking profit of the high dimensional Hilbert space associated to spatial modes. [1] D.J. Richardson, J.M. Fini, L.E. Legario. Nat. Photon. 7 (2013) 354. [2] M. Heinrich, M.A. Miri, S. Stützer, R. El-Ganainy, S. Nolte, A. Szameit, D.N. Christodoulides. Nat. Commun. 5 (2014) 3698. [3] R. Menchon-Enrich, A. Benseny, V. Ahufinger, A.D. Greentree, Th. Busch, J. Mompart. Rep. Prog. Phys. 79 (2016) 074401. [4] G. Queraltó, J. Mompart, V. Ahufinger. Submitted to: Light: Science & Applications. (2017).
        Speaker: Mr. Gerard Queraltó Isach (Universitat Autònoma de Barcelona)
      • 17:45
        SERS sensors made of polymers and Aluminum to check the health of artworks 20m
        Introduction Conservation and restoration of works of art face many problems caused by degradation of bulk materials, varnishes, binding media and dyes. Identification and characterization of these degradation products has always been of high importance because it is the first step to develop and apply the appropriate treatments to preserve our cultural heritage. The concern is more acute for modern and contemporary art, because the materials used are so radically different from those used in classical art, that there is a significant lack of established conservation protocols that can deal with the often extremely fast degradation of materials used by contemporary artists. In this work we show our approach to detect early degradation products of common polymers by means of surface enhanced Raman scattering (SERS) sensors developed in our lab, and based on the fabrication of regular micro and nanostructured polymers coated with a thin layer of aluminum as plasmonic metal. Checking the health of artworks by SERS Raman spectroscopy is a nondestructive method that provides the vibrational fingerprint spectrum of the molecular structure of materials, so it might be the perfect tool to analyze artworks where the sampling is highly restricted. But Raman signal is intrinsically weak due to the low number of scattered photons available for detection. Surface Enhanced Raman Scattering (SERS) comes to help, because it is a method to amplify the Raman signals of molecules by an increment of their apparent Raman cross-section [1]. To do this trick, the excitation laser is shined over metallic nanoparticles or nano-structured metal surfaces, typically made of noble metals, with gold and silver as common choice. The laser resonantly drives the metal surface charges, creating highly localized plasmonic light fields, known as hot-spots. When a molecule is close to one of these hot-spots, a large amplification of its Raman signal can be observed, allowing the detection of very low concentrations of chemical species or even single molecule detection [2]. The main problem to use SERS as everyday lab technique is the lack of appropriate substrates. Few commercial substrates are available, they are expensive and quite unstable, requiring to keep them in controlled atmospheres and careful handling to maintain their enhancing activity. Another problem is repeatability due to variability in size and distribution of nanostructures. To tackle the main drawbacks of SERS substrates we developed an easy and cheap fabrication process in just two steps: replica molding based on ultraviolet nanoimprint lithography (UV-NIL), followed by coating with a thin metal layer by metal evaporation. The molding step guarantees the same shape and structure in all the substrates and the UV-NIL provides freedom to design any 2.5D structure and, in combination with the photoresist used, reduces the fabrication time to just a few seconds. In our case we choose a crosslinkable di- or tetrafunctional perfluoropolyether derivate [3] and a commercial ormocer photoresist. As plasmonic metal we relies on aluminium, initially because its low cost compared to gold or silver and also because the Al2O3 passivation layer, that far from being a problem is an advantage because after reaching a thickness of 1.5 to 3.0 nm it stops growing and protect the metal from further oxidation, while still allows the plasmonic excitation of molecules attached to the surface. Aluminium has properties that enable strong plasmon resonances spanning from the UV to the NIR region [4]. Fig.1. Polymer and Al SERS substrates and SEM image of the periodic nanostructure showing the inverted pyramids geometry and the nanocrystals of Al on the surface. Initial tests where made with organic analytes like Rhodamine 6G, Coumarin 440, Rhodamine B or Crystal Violet, using 514 nm and 785 nm excitation lasers with powers ranging between 0.01-1.0 mW. The signal enhancement is comparable or higher than that obtained with commercial substrates made of gold or silver. Fig.2. SERS spectra of photo-oxidation products of: a) linseed oil and b) polyisoprene rubber. As an actual application we are testing the SERS substrates to detect and identify early degradation products formed by ageing or weathering of modern and contemporary artworks made of different polymers and blends. This diagnostic information is relevant for material science researchers and conservators which can develop and apply appropriate treatments to fight against degradation and preserve valuable cultural heritage goods. The sensibility of SERS substrates is a keystone in a field where sampling is strongly limited due to the value of the pieces. Tests on different polymers, binders, inks, pigments and other materials are yielding promising results those showed in Fig.1b. This work was supported by the European Union (CORDIS) Project NANORESTART (H2020-NMP-21-2014/646063). The authors also thank the financial support by the MEC (MAT2015-67458-P). References [1] E.C. Le Ru, E. Blackie, M. Meyer, and P.G. Etchegoin, J.Phys. Chem. 111 (2007) 13794. [2] K. Kneipp, Y. Wang, H. Kneipp, L.T. Perelman, I. Izkan, R. R. Dasari and M. S. Feld, Phys. Rev. Lett. 78 (1997) 9, 1667. [3] M. Gómez and M. Lazzari, Microelectronic Engineering, 97 (2012) 208. [4] M. W. Knight, N. S. King, L. Liu, H. O. Everitt, P. Nordlander, and N. J. Halas, ACS Nano 8 (2014) 834.
        Speaker: Mr. Manuel Gómez (CIQUS, Center for Research in Biological Chemistry and Molecular Materials, Santiago de Compostela University, 15782, Santiago de Compostela, Galicia, Spain)
      • 18:05
        Testing macroscopic realism with measurements of light polarization 20m
        We study Leggett-Garg inequalities and no-signaling in time to determine the macrorealistic character of light polarization. In particular we present a model based on photon extraction. We show that violations of macrorealism occur for sufficietly invasive measurements, while for sufficiently coarse-grained measurements violations vanish.
        Speaker: Prof. Eugenio Roldán Serrano (Universitat de València)
      • 18:25
        Time-dependent density functional theory of magneto-optical response 20m
        Though the perturbation theory has been successfully used to describe various types of responses of molecules to electromagnetic fields for a long time, the extension of this theory to solids is not straightforward since the position operator is ill defined for such systems. The theoretical description of magnetic fields in periodic systems is particularly challenging as it leads to non-perturbative changes in eigenstates. We present an approach to calculation of magneto-optical response within the density matrix formalism applicable both to molecules and solids. The density matrix perturbation theory is implemented in open-source Octopus code using efficient Sternheimer method for solution of the Liouville equation. The implemented procedures are tested against available literature data for molecular and crystalline systems.
        Speaker: Dr. Irina Lebedeva (Universidad del País Vasco)
        Slides
    • 15:20 18:25
      Particle and Theoretical Physics I Aula Química Técnica (Facultad de Química (USC))

      Aula Química Técnica

      Facultad de Química (USC)

      Conveners: Dr. Isidro González Caballero (Universidad de Oviedo), Dr. JOSE SALT (IFIC), Dr. Santiago Gonzalez de la Hoz (IFIC)
      • 15:25
        Measurement of the CP-violating weak phase φs in Bs0 → (K+π−)(K−π+) decays at LHCb 30m
        The huge abundance asymmetry between matter and antimatter present in our Universe remains as a mystery nowadays. Only the weak interaction (of the four fundamental ones) is known to mediate processes where the Charge-Parity (CP) symmetry is violated (this meaning different production rates for particles and antiparticles). However, the size of this effect is very small, and new sources of CP violation (outside the Standard Model) are searched for. The LHCb experiment, at CERN, is designed to study CP violation in the decays of hadrons containing b (beauty) quarks, produced in proton-proton collisions in the Large Hadron Collider. New heavy particles may enter such processes via “quantum loops”, modifying the properties of the transition and impacting the CP-violating observables. An accurate measurement of such observables can thus hint the presence of New Physics. The decay Bs0 → K∗0(→ K+π−)K ̄∗0(→ K−π+) is a golden channel for LHCb. The observable to be measured in this case is the weak phase φs, arising in the interference between the amplitudes of Bs0 mesons decaying directly into K∗0K ̄∗0 and those decaying after Bs0 − B ̄s0 oscillation. It is possible to generalise this framework to include other (non K∗0) Kπ components in the decay chain, increasing the available statistics and thus the accuracy of the measurement. In this talk, the first analysis aimed at measuring φs in Bs0 → (K+π−)(K−π+) decays, with the Kπ pairs arranged in different spin configurations (0, 1 and 2), is presented.
        Speaker: Mr. Julián García Pardiñas (Universidade de Santiago de Compostela)
        Slides
      • 15:55
        Search for Higgs boson production in association with a top-antitop quark pair in CMS 30m
        A search for a Higgs boson production in assotiation with a top-antitop quark pair is presented in pp collisions at $\sqrt{s} = $ 13 TeV recorded by CMS. We target topologies in which the scalar boson decays into $WW^*$, $ZZ^*$ and $\tau\tau$ and at least one of the top quarks decays leptonically by selecting events with two same-sign, three or four leptons in the final state. The search results in a measured cross-section of $1.5 \pm 0.5$ times the expectations of the Standard Model, which corresponds to 3 standard deviations with respect to the no $t\bar{t}H$ production hypothesis.
        Speaker: Sergio Sanchez Cruz (Universidad de Oviedo)
        Slides
      • 16:25
        Measurement of polarisation fractions and CP asymmetries in charmless B0(s) decays at LHCb 30m
        Within the Standard Model (SM) framework, charmless b decays proceeding via tree diagrams are suppressed by the smallness of the |Vub| term in the CKM matrix. Their contribution to the final decay rate is, therefore, of a similar order of magnitude of the otherwise sub-leading penguin process. This situation enhances the interference effects between the two processes and allows the measurement of their relative weak phase difference. The relative importance of the penguin diagrams in charmless processes could allow the detection of new particles entering in the loops which would cause deviations from the branching fractions and CP asymmetries predicted by the SM. The LHCb detector consists of a single-arm forward spectrometer specifically designed for flavour physics. The characteristics of this design include a very good vertex and tracking resolution, a fully instrumented forward coverage that maximizes the acceptance of the bb quark pairs produced at the LHC and a very efficient particle identification (PID) system separating protons, pions and kaons in the full acceptance. Together with a high performing trigger, these vertexing and PID efficiencies are crucial in order to study flavour physics in the very complicated hadronic environment of the LHC. In this talk the latest results on charmless b decays by the LHCb collaboration will be presented, with particular emphasis on the amplitude analysis of the B0->(pi pi)(K pi) decay. This includes the multidimensional analysis of the invariant masses and helicity angles, which allows to measure the polarisation fractions, direct CP violation and triple product asymmetries
        Speaker: Mrs. María Vieites Díaz (Universidade de Santiago de Compostela)
        Slides
      • 16:55
        The light detection system for the WA105/ProtoDUNE-DP neutrino detector at CERN 30m
        Short description of the two prototypes of the WA105 experiment. Description of the light detection system for the experiment. Main results of the PMTs characterization.
        Speaker: Ms. Chiara Filomena Lastoria (CIEMAT (Madrid))
      • 17:25
        Photon Polarization in Radiative Bs Decays at LHCb 30m
        The photon polarization in radiative Bs decays has been studied for the first time at LHCb using Run I data. Also it is discuss the ongoing analysis using Run II data, the time-dependent analysis of the Bs→φγ decay rate adding the information of the flavour of the Bs candidates at production.
        Speaker: Mrs. Clara Remon Alepuz (PhD Student)
        Slides
      • 17:55
        Unitarized EFT for a strongly interacting BSM Electroweak Sector coupled with ttbar 30m
        We use the nonlinear electroweak chiral Lagrangian (EChL) and the mathematical properties of the S-matrix (encoded into unitarization methods) for sampling the collider phenomenology of a (hypothetical) strongly interacting electroweak symmetry breaking sector (EWSBS) coupled with ttbar states. The EChL Lagrangian is used as an intermediate energy approximation (E~500 GeV), where the Equivalence Theorem is valid but the EFT does not violate unitarity. Of highest interest is the EWSBS and the description of the scattering processes between longitudinally polarized gauge bosons and the Higgs-like particle discovered at the LHC. Because ttbar channel is more accessible at the LHC, we couple such processes with ttbar. Hence, we use the A[W_L,Z_L,h-->W_L,Z_L,h] scattering amplitudes computed at NLO, and consider a weak (perturbative) coupling with ttbar states, in order to compute the A[W_L,Z_L,h-->t tbar] scattering amplitudes. Unitarization procedures are used to extend the validity range of the EFT up to the first resonance, where the EFT perturbative expansion breaks down. We develop a modified version of several unitarization procedures in order to simplify the computation by considering that coupling with ttbar states is perturbative..
        Speaker: Dr. Rafael Delgado López (Complutense University of Madrid)
        Slides
        Video
    • 15:30 19:10
      Física Médica II Aula Química Orgánica (Facultad de Química (USC))

      Aula Química Orgánica

      Facultad de Química (USC)

      • 15:30
        Bioimagen coherent en free-electron lasers: éxitos y retos 15m
        Los free-electron lasers han supuesto una gran revolución en el ámbito de la imagen coherente, permitiendo explorar simultáneamente resoluciones espaciales y temporales en torno al ångström y el femtosegundo. Además, dado que generan un haz coherente en el espectro de los rayos X, permiten utilizar técnicas de imagen coherente similares a las utilizadas con láseres en el visible. Concretamente, estas técnicas tienen el potencial de fotografiar células y sistemas biológicos con resoluciones atómicas y filmar películas de procesos con 10 15 fotogramas por segundo. En esta presentación discutiremos los últimos resultados obtenidos con técnicas coherentes desarrolladas para obtener imágenes de sistemas biológicos en free-electron lasers. Finalmente, mencionaremos las limitaciones, retos y posibles soluciones de estas técnicas utilizadas en free-electron lasers para bioimagen.
        Speaker: Dr. Pablo Villanueva Perez (DESY-CFEL)
        Slides
      • 15:45
        Complete Validation of Biograph mCT PET with Monte Carlo simulation: GATE and STIR. 15m
        The Geant Application for Tomographic Emission (GATE) is a simulation platform based on GEANT4, which is designed to perform numerical simulation in medical imaging and radiotherapy. The purpose of our study is to validate a GATE model of the commercial PET/CT Siemens Biograph placed at the University Hospital of Salamanca (Spain). The geometry of the system was implemented including the detector ring, crystal blocks, PMTs,etc. The GATE simulation results were reconstructed with analytical and iterative algorithms using STIR (Software for Tomographic Image Recostruction), an open source software for 3D PET and SPECT image reconstruction. Simulated data were compared to experimental results obtanied using the NEMA NU-2-2007 standard protocols. It consisted of sensitivity estimation, count rate, NEC curve, scatter fraction, spatial resolution and image quality (hot and cold contrasts, atenuation in the lung and percent background variability). The reults for 2D and 3D sensitivity, scatter fraction, count rate and parameters referring to the image quality were found to agree with experimental values. The simulated sensitivity obtained is 10.9 cps/kBq in the center of the transaxial field of view and 8.85 cps/kBq at 10cm. Excellent agreement between simulation and experiment can be seen in the spatial resolution results, FWHM being 5.288 mm at 1 cm with GATE and 5.280 mm at 1 cm experimentally. Simulated Scatter dispersion was 35.1% for a concentration of 2.48 kBq/mL, a value was lower than that provided by the manufacturer. In conclusion, our study showed that our Monte Carlo model can be used to optimize,simplify and reduce the simulation time for the quality control procedure of PET scanners.
        Speaker: Ms. Lorena Vázquez Canelas (Universidad de Salamanca)
        Diapositivas
      • 16:00
        High throughput production of solid targets for laser-driven particles acceleration through MEMS based processing. 15m
        Laser-driven particle acceleration is reasonably feeding the hope for the development of compact particle accelerators relying on the ultra-intense interaction established when a high power, ultra-short, laser (HPL) pulse is focused on a very tiny area of a solid target surface. [1]. Laser-driven ion acceleration has been observed since early experiments of solid target irradiation with lasers, and it has been explained in the framework of Target Normal Sheath Acceleration (TNSA) model. Particle acceleration originates from the rear surface of a solid target, typically a thin metallic foil, and is caused by the charge separation field generated by laser-plasma interaction on the front target surface at laser intensities of 1018÷1020 W/cm2 (Fig.1 (a)). Until now, targets supply strategies have been principally based on fabrication and assembly on an individual basis. However, this approach is not suitable to exploit the full potential of high repetition rate HPLs. Therefore, the development of high throughput target fabrication processing for ultra-intense laser-plasma experiments is receiving many efforts. In this regard, the approach based on micro-/nano-electromechanical systems (N/MEMS) technology, which evolved from semiconductor device manufacturing, is a very attractive solution [2]. It provides, in fact, parallel processing and the possibility to achieve complex target design with micro-nano sized features on a variety of materials. Here, we present the fabrication of thin layer membranes made by aluminum, both free-standing and supported by a nanometric thickness of SiO2, embedded in a silicon frame. Membranes were fabricated with variable SiO2 and aluminum thicknesses according the route schematized in Fig. 1(b), which combines photolithography, thin layer deposition techniques, wet and dry etching. Both wafer sides were processed in such a way to obtain, on front side, the openings for the aluminum membranes which are then deposited by sputtering on the back side, with thicknesses equal to 0.25, 0.5 and 1 micron, respectively. Some of the obtained targets are shown in Fig.1(c) characterized by optical, electron, and confocal microscopy. Individual targets contain up to 16, 1 mm2 membranes available for experiments, and were used for laser-plasma experiments at the laser installation of Proton Laser Applications, S.L., which has developed a table-top laser system running at 3 TW with an intrinsic repetition rate up to 100 Hz [3]. The experimental setup is schematized in Fig. 1(d) showing in detail the interaction chamber where targets are easily located thanks to a purpose made holder which carries up to 16 individual targets, resulting in 256 membranes available for consecutive shots. Results of preliminary experiments, represented in Fig.1 (e) for 0.5 μm aluminum membranes, show the achievement of successful proton acceleration up to 2 MeV almost constant within the spanned focal plane (distances from focus position are listed in the legend, in microns), and having the peak value in the focus, as expected. This maximum energy is slightly higher than previous results from plain foils, and corresponds to the expectations with respect to the laser energy on target. We expect to improve this performance by further developments of our system directed from one side to increase the laser pulse energy, and from the other, to involve more sophisticated target designs with micro-nano texturized surfaces which, according to particle-in-cell simulations [4], should improve the coupling, and thus, the acceleration results.
        Speaker: Dr. rosa letizia zaffino (instituto de microelectronica de barcelona, IMB-CNM)
        Slides
      • 16:15
        Design concept and pilot tests of dedicated two panels prostate PET 15m
        The main goal of this project (called PROSPET) is the development of a PET system for early diagnostic, treatment and following prostate cancer (PCa). It will also allow us for PCa biopsy guiding using real time PET. We aim to significantly improve the efficiency and the spatial resolution in the detection of PCa, when compared to whole body PET scanners. The design of this dedicated PET is based on two panels of detectors surrounding the patient abdomen (nearing the hip). In order to estimate the improvement and to evaluate possible artefacts due to the particular design, we have run simulations using GATE, a Geant4 platform.
        Speaker: Mr. Cañizares-Ledo Gabriel (I3M)
      • 16:30
        Electromagnetic metamaterials for magnetic resonance imaging in medicine 15m
        Metamaterials are artificial composites whose electromagnetic properties can be engineered to achieve any value of effective permittivity and/or permeability. Metamaterials can be designed with a negative permittivity/permeability to behave as a lens for the electric/ magnetic field. The ability of metamaterial lenses with negative permeability to increase the signal-to-noise ratio (SNR) in magnetic resonance imaging (MRI) has been investigated. Moreover, it has been also analyzed the ability of metamaterial slabs with zero/high permeability to reject/confine the RF magnetic field in MRI systems and thus to locally increase the SNR. Finally, the ability of metamaterial lenses to localize the field of view of MRI coils in an array and thus to reduce the noise correlation has been also investigated. This has application in parallel MRI to reduce the acquisition time of the image.
        Speaker: Prof. Manuel Freire (Universidad de Sevilla)
      • 16:45
        Coffee break 30m
      • 17:15
        Estimación del ángulo de Cobb con métodos aprendizaje máquina a partir de imágenes topográficas de la superficie de la espalda, obtenidas con luz estructurada 15m
        El aprendizaje máquina (machine learning) ofrece algoritmos y procedimientos inteligentes para abordar análisis complejos de datos, los cuales han servido para la implementación de sistemas de ayuda a la decisión en una variedad de aplicaciones dentro de diversas áreas médicas. En este trabajo se ha aplicado para el diagnóstico y seguimiento de la escoliosis idiopática. Esta patología frecuente en la adolescencia se caracterizada por el valor del ángulo de Cobb medido en la radiografía del paciente. Ahora bien, la dosis repetida de radiación ionizante, a la cual están expuestos estos pacientes en edades más radiosensibles, puede representar riesgos para su salud futura. La topografía de superficie de la espalda es una propuesta que la propia SOSORT (International Society on Scoliosis Orthopaedic Rehabilitation and Treatment) resalta como prueba complementaria para documentar la deformidad asociada con la escoliosis. No obstante, existen diversas técnicas topográficas que tratan de valorar la deformidad, mediante índices topográficos diferentes, por lo que muchas veces no son comparables entre sí y no facilita un consenso para que estas técnicas sean útiles en la práctica clínica habitual. Por ello, el objetivo de este trabajo es la utilización de modelos de aprendizaje máquina para estimar el ángulo de Cobb a partir de variables topográficas obtenidas con un método no lesivo basado en la proyección de luz estructurada. El modelo con mejores resultados ha sido el Random forest (RF). Los valores estimados del ángulo de Cobb con este modelo, aplicado a todos los casos, permite clasificar a los pacientes como patológicos si el Cobb calculado es mayor o igual a 10º, con índices de fiabilidad diagnóstica: sensibilidad=0.97, especificidad=0.79, valor predictivo positivo=0.92 y valor predictivo negativo=0.91, que avalan la capacidad diagnóstica del método.
        Speaker: Dr. Rosa M Cibrian (Biofísica y Física Médica. Dpto. de Fisiología. Universitat de València)
      • 17:30
        Estimation of the radiobiological impact on non-small-cell lung cancer treatment plannings due to dose calculation algorithm 15m
        Introduction The modeling of tissue heterogeneities and photon fluences for complex treatment plans in radiotherapy has been reported as the main source of discrepancy in dose calculation [1]. Dose distribution disagreements between Monte Carlo (MC) and treatment planning system (TPS) calculations produce significant variations in the estimation of tumor control probability (TCP) [2]. Hence for a complete treatment planification including radiobiological parameters we have to obtain an accurate calculation of the dose distribution. Our purpose is to assess radiobiological variations of lung cancer treatment plans due to divergences between dose distributions calculated by Pinnacle³ TPS (version 9.8), employed at the Hospital Universitario Virgen Macarena (Seville, Spain), and by the Geant4 MC toolkit (version 10.01.p01) [3,4]. Material and methods Three clinical cases (see Table 1) distinguished by their tumoral size and localization were analysed. Each clinical case presents a treatment planification composed by 6 MV photon beams with a conventional fractionation, i. e. 2 Gy per fraction. This scheme was established in order to achieve a 66 Gy prescribed dose to the 95% of the planning target volume (PTV). We have set conformity index (CI) and homogeneity index (HI) [5] as key parameters for dose distribution comparisons between Pinnacle3 and Geant4. In addition to this dose analysis, we have calculated TCP according to the lineal-quadratic (LQ) model [6]. For this task we have used an alpha value of 0.3 Gy-1, a beta value of 0.03 Gy-2 and a density of clonogenic cells of 10^7 cells/cm3. For TPS calculations we have applied the Collapsed Cone algorithm and a voxel resolution of 2 x 2 x 2 mm³. In our MC calculations we have simulated 2•10^10 events per clinical case. The scoring volume dimensions were equal to patient DICOM image files resolution, i. e. 0.937 x 0.937 x 5 mm³. These files were exported from the TPS for every single treatment plan. Results In Table 2 we have summarized the CI, HI and TCP values calculated with Geant4 and Pinnacle3 for each clinical case. Furthermore, we have obtained variations of absorbed dose at the 95% of the PTV (between Geant4 and TPS dose calculations) up to 2.3 Gy for the clinical case 1. In this case, a gamma analysis [7] between calculated dose distributions with Geant4 and TPS (Fig. 1), done with acceptance criteria of 3%-3mm, gave a passing rate of 78.3% within the patient. This evaluation was done utilizing Monte Carlo Treatment Planning (MCTP) CARMEN [8,9]. Discusion and conclusions In all clinical cases we have found more heterogeneous dose distributions employing Geant4 as calculation system. HI and CI values show us that dose calculations depend on the particular clinical case. For clinical case 1 we have done a gamma analysis (3%-3 mm), which shows high discrepancies (red points which do not satisfied gamma criteria) at the dose maximum zone which is inside PTV. Dose divergences, expressed through HI and CI values, gave variations in TCP close to 4% between Geant4 and TPS calculations. In our methodology we have used the LQ model with an alpha/beta ratio of 10 Gy and a constant clonogenic cells density of 10^7 cells/cm3. A further study including more sophisticated radiobiology models and hypofractionated radiotherapy schemes will is ongoing. Acknowledgments This work was funded in part by the Spanish Ministry of Economy and Competitiveness (under projects no. FPA2014-53290-C2-2-P and FPA2016-77689-C2-1-R) and by Junta de Andalucía (under project no. P12-FQM-1605). The MC simulations were performed with our FIS-ATOM computing cluster, hosted at Centro Informático y Científico de Andalucía (CICA, Seville, Spain). References [1] B. Vanderstraeten, et al. Medical Physics 33 (2006) 3149. [2] I. J. Chetty et al. Radiother. Oncol. 109 (2013) 498. [3] S. Agostinelli et al. Nucl. Instrum. Meth. A 506 (2003) 250. [4] J. Allison et al. Nucl. Instrum. Meth. A 835 (2016) 225. [5] ICRU Report 83. Prescribing, recording, and reporting intensity-modulated photon-beam therapy (IMRT). 2010. [6] J. F. Fowler Br. J. Radiol. 62 (1989) 679. [7] D. Low et al. Medical Physics 25 (1998) 656. [8] A. Ureba et al. Medical Physics 41 (2014) 081719-1. [9] J. A. Baeza et al. Medical Physics 42 (2015) SU-E-T-157.
        Speaker: Mr. Álvaro Perales (Universidad de Sevilla)
        Slides
      • 17:45
        Aplicación de métricas de distancia en el análisis de imágenes de bandas oligoclonales para el diagnóstico precoz de la Esclerosis Múltiple 15m
        El trabajo que se presenta comprende el diseño y evaluación inicial de nuevos biomarcadores de esclerosis múltiple mediante análisis de las bandas oligoclonales obtenidas a partir de la digitalización y procesado de las imágenes de membranas electroforéticas en una prueba estándar. Se comparan las secuencias de bandas de pacientes con diagnóstico inicial de síndrome neurológico aislado para predecir su evolución hacia esclerosis múltiple clínicamente definida mediante múltiples métricas de distancia.
        Speaker: Dr. Marina Rosales-Martinez (Universidad de Sevilla)
        Slides