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Topologically protected edge and junction states, previously predicted, have recently been observed in armchair graphene nanoribbon (AGNR) heterojunctions. Here, via tight-binding-based calculations, we explain the relation between the nature and number of the zero-mode edge states of finite-length AGNRs and their structure, topological invariants, and winding number. This allows us to rationalize the design of AGNR heterojunctions and superlattices with tailored phases. We show how the choice of widths, interface coupling geometry, and boundaries determines the emergence of topological states following patterns that depend on the structure and family of the constituent AGNRs. Furthermore, we prove that quantum-well-like states confined in one of the constituent ribbons develop in all the AGNR junctions irrespective of their trivial or topological character. The bipartite nature of the honeycomb lattice is determinant for the topological properties of the junctions: their electronic states can be topologically trivial or nontrivial depending on subtle differences at the boundaries of the ribbons., Spanish MINECO under Grant No. PGC2018-099199-B-I00 and the European Union structural funds and the Comunidad Autónoma de Madrid (CAM) NMAT2D-CM Program (S2018-NMT-4511). M.C.M. acknowledges financial support of Spanish MINECO under Grant No. RTI2018-097895-BC41 and the FEDER Program of the European Union.

The electronic properties of antimonene, single-layer Sb, are attracting great attention. In this paper, spin transport in armchair antimonene nanoribbon (ASbNR) is investigated. Following the tight-binding model, we calculate both the transmission probability and the conductance by means of the nonequilibrium Green's function (NEGF) method. The effects of an external electric field vertical to the ribbon plane are explored. Our results indicate that the spin-flip rate increases with the vertical electric field. Disorder effects on the spin transport are addressed by considering the presence of charged impurities. It is found that charged impurities also enhance the spin-flip rate but to a lesser extent than the out-of-plane electric field., Spanish MINECO Grant No. PGC2018-099199- B-I00, the European Union Structural Funds, and the Comunidad de Madrid NMAT2DCM Program (Grant No. S2018-NMT-4511).

We analyze the localization properties of two-dimensional systems based on partite lattices with a basis. Contrary to standard results, we find that a band of critical states emerges for systems in the unitary class A preserving spin symmetry when disorder is unevenly distributed over the basis atoms. The critical metal arises when the less disordered sublattice is connected and has time-reversal symmetry broken. The unexpected robustness to disorder presented here is an appealing result which can be measured in optical lattices., FCT (Portugal) through Grant No. EXPL/FIS-NAN/1728/2013. This research was supported in part by the Spanish MINECO Grants No. FIS2014-57432-P and No. PGC2018-099199- B-I00, the European Union Structural Funds, and the Comunidad de Madrid NMAT2D-CM Program (Grant No. S2018-NMT-4511).

Presentation held by M. Pilar López Sancho (Instituto de Ciencia de Materiales de Madrid - CSIC) during the conference "Structural gender change at universities and research funding organizations", an event of H2020 project SUPERA. Madrid, 16/11/2018

The band structures of single-layer ${\mathrm{MoS}}_{2}$ and ${\mathrm{WS}}_{2}$ present a coupling between spin and valley degrees of freedom that suppresses spin-flip scattering and spin dephasing. Here we show that out-of-plane deformations, such as corrugations or ripples, enhance spin-flip scattering in armchair ${\mathrm{MoS}}_{2}$ and ${\mathrm{WS}}_{2}$ nanoribbons. Spin transport in the presence of surface roughness is systematically investigated, employing the nonequilibrium Green's function method along with the tight-binding approximation. Both transmission and conductance have been calculated as a function of surface roughness. Our results indicate that the spin-flip rate, usually neglected in flat pristine samples, increases significantly with the surface roughness amplitude. These results are important for the design and fabrication of transition metal dichalcogenides based spintronic devices.

Single- and few-layer transition metal dichalcogenides have recently emerged as a new family of layered crystals with great interest , not only from the fundamental point of view, but also because of their potential application in ultrathin devices. Here the electronic properties of semiconducting MX2, where M =Mo or W and X = S or Se, are reviewed. Based on of density functional theory calculations, which include the effect of spin-orbit interaction, the band structure of single-layer, bilayer and bulk compounds is discussed. The band structure of these compounds is highly sensitive to elastic deformations, and it is reviewed how strain engineering can be used to manipulate and tune the electronic and optical properties of those materials. Further, the effect of disorder and imperfections in the lattice structure and their effect on the optical and transport properties of MX2 is discussed. The superconducting transition in these compounds, which has been observed experimentally, is analyzed, as well as the different mechanisms proposed so far to explain the pairing. Finally, a discussion on the excitonic effects which are present in these systems is included.

Topological matter is a trending topic in condensed matter: From a fundamental point of view, it has introduced new phenomena and tools and, for technological applications, it holds the promise of basic stable quantum computing. Similarly, the physics of localization by disorder, an old paradigm of obvious technological importance in the field, continues to reveal surprises when new properties of matter appear. This work deals with the localization behavior of electronic systems based on partite lattices, with special attention to the role of topology. We find an unexpected result from the point of view of localization properties: A robust topological metallic state characterized by a nonquantized Hall conductivity arises from strong disorder in topological systems based on bipartite lattices. The key issue is the nature of the disorder realization: selective disorder in only one sublattice. The generality of the result is based on the partite nature of most recent two-dimensional materials such as graphene or transition-metal dichalcogenides, and the possibility of the physical realization of the particular disorder demonstrated in Ugeda et al. [M. M. Ugeda et al., Phys. Rev. Lett. 104, 096804 (2010)] and Zhao et al. [L. Zhao et al., Science 333, 999 (2011)]., E.C. acknowledges the financial support of FCT-Portugal through Grant No. EXPL/FISNAN/1728/2013. This research was supported in part by the Spanish MECD Grant No. FIS2014-57432-P, the European Union structural funds, and the Comunidad de Madrid MAD2D-CM Program (S2013/MIT-3007), as well as the European Union Seventh Framework Programme under Grant Agreement No. 604391 Graphene Flagship FPA2012-32828. S2013/MIT-3007/MAD2D-CM info:eu-repo/grantAgreement/EC/FP7/604391

[EN] Objective: To analyse gender inequalities in research on public health and epidemiology in Spain for theperiod 2007-2014.Method: A descriptive study was conducted by sex of leadership positions in the Centre for BiomedicalResearch Network (CIBER), especially in the subject area of epidemiology and public health (CIBERESP) in2014; scientific societies of public health (SESPAS) and epidemiology (SEE) 2009-2014; research projectsrequested (13,320) and financed (4,699), and monetary amounts of calls for Strategic Action in Health(AES), 2007-2013. Results: Women were clearly under-represented in positions of leadership and in research excellencein public health (CIBER), with a predominance of men in decision-making positions. Although researchprojects led by women in AES increased slightly between 2007 and 2013, among proposed projects thisfigure was less than 50%, with the exception of the public health commission. The gender gap was even greater in funded projects. Projects led by men were more likely to be funded, representing 29% in publichealth. There was also a persistence of horizontal gender segregation in positions of scientific recognitionin the SESPAS and SEE Congresses. Conclusions: The over representation of male leaders in public health research in Spain can be understoodas an indicator and a consequence of androcentrism in scientific societies and professional groups. Thissexist situation threatens the existence of innovative products and services from a gender perspectivethat respond to the needs and demands of society as a whole. More women are needed in researchincorporating this perspective.© 2015 SESPAS. Published by Elsevier España, S.L.U. All rights reserved., [ES] Objetivo: Analizar las desigualdades de género en investigación en salud pública y epidemiología enEspañaa, en el periodo 2007-2014.Método: Estudio descriptivo según sexo de posiciones de liderazgo del Centro de Investigación Biomédicaen Red (CIBER), especialmente en el área temática de epidemiología y salud pública (CIBERESP) en 2014;de sociedades científicas de salud pública (SESPAS) y epidemiología (SEE), 2009-2014; y de proyectos deinvestigación solicitados (13.320) y financiados (4699), e importes de convocatorias de Acción Estratégica en Salud (AES), 2007-2013. Resultados: Existe una clara infrarrepresentación de mujeres líderes y contratadas en investigación deexcelencia en salud pública (CIBERESP), con predominio de los hombres en puestos de decisión. Aunque los proyectos de investigación de la Acción Estratégica en Salud (AES) liderados por mujeres han crecido ligeramente entre 2007 y 2013, entre los solicitados no alcanzan el 50%, con excepción de los de la Comisión de Salud Pública. La brecha de género es aún mayor en proyectos financiados. Los proyectos liderados por hombres tienen mayor probabilidad de obtener financiación, alcanzando el 29% en los desalud pública. Persiste una segregación horizontal de género en posiciones de reconocimiento científicoen congresos de SESPAS y SEE. Conclusiones: La sobrerrepresentación de líderes masculinos en la investigación en salud pública en España debe entenderse como indicador y consecuencia del androcentrismo en las sociedades científicasy los grupos profesionales. Esta situación sexista pone en riesgo la existencia de productos y serviciosinnovadores desde la perspectiva de género que den respuestas a necesidades y demandas de toda lasociedad. Se necesitan más mujeres en investigación que tengan incorporada esta perspectiva.© 2015 SESPAS. Publicado por Elsevier España, S.L.U. Todos los derechos reservados, Este trabajo ha recibido financiación parcial de la Acción Estratégica en Salud del Instituto de Salud Carlos III (Exp. PI12/00498) yFondos FEDER.

To analyse gender inequalities in research on public health and epidemiology in Spain for the period 2007-2014.A descriptive study was conducted by sex of leadership positions in the Centre for Biomedical Research Network (CIBER), especially in the subject area of epidemiology and public health (CIBERESP) in 2014; scientific societies of public health (SESPAS) and epidemiology (SEE) 2009-2014; research projects requested (13,320) and financed (4,699), and monetary amounts of calls for Strategic Action in Health (AES), 2007-2013.Women were clearly under-represented in positions of leadership and in research excellence in public health (CIBER), with a predominance of men in decision-making positions. Although research projects led by women in AES increased slightly between 2007 and 2013, among proposed projects this figure was less than 50%, with the exception of the public health commission. The gender gap was even greater in funded projects. Projects led by men were more likely to be funded, representing 29% in public health. There was also a persistence of horizontal gender segregation in positions of scientific recognition in the SESPAS and SEE Congresses.The overrepresentation of male leaders in public health research in Spain can be understood as an indicator and a consequence of androcentrism in scientific societies and professional groups. This sexist situation threatens the existence of innovative products and services from a gender perspective that respond to the needs and demands of society as a whole. More women are needed in research incorporating this perspective.

We analyze the topological transition and localization evolution of disordered two-dimensional systems with nontrivial topology based on bipartite lattices. Chern insulators with broken time-reversal symmetry show nonstandard behavior for disorder realizations selectively distributed on only one of the sublattices. The Chern number survives to a much stronger disorder strength (one order of magnitude higher) than in the equally distributed disordered case, and the final state in the strongly disordered case is metallic., E.C. acknowledges the financial support of Fundação para a Ciência e a Tecnologia (FCT)-Portugal through Grant No. EXPL/FIS-NAN/1720/2013. This research was supported in part by the Spanish Ministerio de Educación, Cultura y Deporte (MECD) Grants No. FIS2011-23713 and No. PIB2010BZ-00512, the Comunidad Autónoma de Madrid (CAM) MAD2D-CM Program (S2013/MIT-3007), and the European Union Seventh Framework Programme under Grant Agreement No. 604391 Graphene Flagship FPA2012-32828agship. info:eu-repo/grantAgreement/EC/FP7/604391

[EN] The zero energy modes induced by vacancies in ABC-stacked trilayer graphene are investigated. Depending on the position of the vacancy, a new zero energy solution is realised, different from those obtained in multilayer compounds with Bernal stacking. The electronic modification induced in the sample by the new vacancy states is characterised by computing the local density of states and their localisation properties are studied by the inverse participation ratio. We also analyse the situation in the presence of a gap in the spectrum due to a perpendicular electric field., Support from the Spanish Ministry of Science and Innovation (MICINN) through grants PIB2010BZ-00512 and FIS2011-23713 is acknowledged

2 pages, 3 tables.-- En: Women in Physics, 2nd lUPAP International Conference, AIP Conference Proceedings 795, New York.-- PACS: 01.78+p, 01.85.+f, We present activities of the group, Spanish Women in Physics, during the past three years. We describe measures adopted by the Spanish government to attain gender equality and discuss the status of women in the scientific field. Finally, we present statistical data updated from the last IUPAP Women in Physics Conference in 2005. The percentage of women at various staff levels at universities and at the Consejo Superior de Investigaciones Científicas (CSIC) remains constant (approximately 32%). At CSIC, however, an increase in the number of available posts has led to an increase in the number of women in top positions. The most remarkable finding from Spanish universities is that 50% of women were hired at the new professorial category of “PhD contract.”

[EN] We analyze the deformations of the Fermi surface induced by electron-electron interactions in anisotropic two-dimensional systems. We use perturbation theory to treat, on the same footing, the regular and singular regions of the Fermi surface. It is shown that, even for weak local coupling, the self-energy presents a nontrivial behavior showing momentum dependence and interplay with the Fermi surface shape. Our scheme gives simple analytical expressions based on local features of the Fermi surface. © EDP Sciences., Funding from MCyT (Spain) through grant FIS2005-05478-C02-01 is acknowledged. RR and FG would like to acknowledge the hospitality of Boston University, where part of this work was done.