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Ecological flexibility, extended lifespans, and large brains have long intrigued evolutionary biologists, and comparative genomics offers an efficient and effective tool for generating new insights into the evolution of such traits. Studies of capuchin monkeys are particularly well situated to shed light on the selective pressures and genetic underpinnings of local adaptation to diverse habitats, longevity, and brain development. Distributed widely across Central and South America, they are inventive and extractive foragers, known for their sensorimotor intelligence. Capuchins have among the largest relative brain size of any monkey and a lifespan that exceeds 50 y, despite their small (3 to 5 kg) body size. We assemble and annotate a de novo reference genome for Cebus imitator. Through high-depth sequencing of DNA derived from blood, various tissues, and feces via fluorescence-activated cell sorting (fecalFACS) to isolate monkey epithelial cells, we compared genomes of capuchin populations from tropical dry forests and lowland rainforests and identified population divergence in genes involved in water balance, kidney function, and metabolism. Through a comparative genomics approach spanning a wide diversity of mammals, we identified genes under positive selection associated with longevity and brain development. Additionally, we provide a technological advancement in the use of noninvasive genomics for studies of free-ranging mammals. Our intra- and interspecific comparative study of capuchin genomics provides insights into processes underlying local adaptation to diverse and physiologically challenging environments, as well as the molecular basis of brain evolution and longevity., Funding was provided by Washington University in St. Louis, the Canada Research Chairs Program, and a National Sciences and Engineering Research Council of Canada Discovery Grant (to A.D.M.); the Alberta Children’s Hospital Research Institute (A.D.M., J.D.O., and M.C.J.); the Beatriu de Pinós postdoctoral programme of the Government of Catalonia’s Secretariat for Universities and Research of the Ministry of Economy and Knowledge 2017 BP 00265 (to J.D.O.); and the Japan Society for the Promotion of Science 15H02421 and 18H04005 (to S.K.). This work was partly funded by a Methuselah Foundation grant (to J.P.d.M.); and the Comisión Nacional de Investigación Científica y Tecnológica Chile through the doctoral studentship number 21170433 and the scholarship from the Higher Education Quality Improvement Program (MECESUP) AUS 2003 (to D.T.-M.). GenAge is funded by a Biotechnology and Biological Sciences Research Council Grant BB/R014949/1 (to J.P.d.M.). T.M.-B. is supported by funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 864203), BFU2017-86471-P (MINECO/FEDER, UE), “Unidad de Excelencia María de Maeztu”, funded by the Agencia Estatal de Investigación (CEX2018-000792-M), Howard Hughes International Early Career, Obra Social “La Caixa” and Secretaria d’Universitats i Recerca and CERCA Programme del Departament d’Economia i Coneixement de la Generalitat de Catalunya (GRC 2017 SGR 880). C.F. is supported by the “La Caixa” doctoral fellowship program. E.L. is supported by CGL2017-82654-P (MINECO/FEDER, UE). M.C.J. is supported by funding from the Natural Environment Research Council (NE/T000341/1)., With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2018-000792-M).

The superconducting condensate in a bilayer normal-metal–superconducting film has a nonuniform dependence throughout the layer. For sufficiently thin normal metallic films, the superconducting correlations induced by the contacting superconducting layer result in the formation of a minigap and the characteristic length scales governing the response of the condensate will be different. In this work we use scanning tunneling spectroscopy to visualize the vortex states as a function of the applied magnetic field in a Au-MoGe nanostructure. By comparing the obtained zero-bias conductance maps with time-dependent Ginzburg-Landau simulations, we directly confirm that the observed vortex distributions can only be explained by taking into account the impact of the normal metallic layer. We illustrate this impact on the vortex state for two lithographically fabricated mesoscopic bilayer structures containing an identical antidot array but having different lateral sizes., R.P., B.R, V.V.M., and J.V.d.V. acknowledge support from the Methusalem funding by the Flemish government and the Flemish Science Foundation (Grant No. G0B5315N). C.X. acknowledges support by the National Natural Science Foundation of China (Grant No. 11702218) and the Natural Science Basic Research Plan in Shaanxi Province of China (Grant No. 2018JM1003). This work has been supported by the COST action NanoCoHybri (Grant No. CA16218).

We present experimental and theoretical results of noise-induced attractor hopping between dynamical states found in a single transverse mode vertical-cavity surface-emitting laser (VCSEL) subject to parallel optical injection. These transitions involve dynamical states with different polarizations of the light emitted by the VCSEL. We report an experimental map identifying, in the injected power-frequency detuning plane, regions where attractor hopping between two, or even three, different states occur. The transition between these behaviors is characterized by using residence time distributions. We find multistability regions that are characterized by heavy-tailed residence time distributions. These distributions are characterized by a -1.83±0.17 power law. Between these regions we find coherence enhancement of noise-induced attractor hopping in which transitions between states occur regularly. Simulation results show that frequency detuning variations and spontaneous emission noise play a role in causing switching between attractors. We also find attractor hopping between chaotic states with different polarization properties. In this case, simulation results show that spontaneous emission noise inherent to the VCSEL is enough to induce this hopping., This work has been funded by the Ministerio de Economía y Competitividad (MINECO/FEDER, UE), Spain under project TEC2015-65212-C3-1-P. A.Q. acknowledges FWO for support from a Postdoc fellowship and K.P. is grateful to the Methusalem Foundation for financial support.

Polarization switching in a long-wavelength vertical-cavity surface-emitting laser (VCSEL) under parallel optical injection is analyzed in a theoretical and experimental way. For the first time, to our knowledge, we report experimentally a state in which injection locking of the parallel polarization and excitation of the free-running orthogonal polarization of the VCSEL are simultaneously obtained. We obtain very simple analytical expressions that describe both linear polarizations. We show that the power of both linear polarizations depend linearly on the injected power in such a way that the total power emitted by the VCSEL is constant. We perform a linear stability analysis of this solution to characterize the region of parameters in which it can be observed. Our measurements qualitatively confirm the previous theoretical predictions., Ministerio de Economía y Competitividad (MINECO/FEDER) (TEC2015-65212-C3-1-P); Fonds Wetenschappelijk Onderzoek (FWO); Methusalem Foundation.

We determine the spin-lifetime anisotropy of spin-polarized carriers in graphene. In contrast to prior approaches, our method does not require large out-of-plane magnetic fields and thus it is reliable for both low-and high-carrier densities. We first determine the in-plane spin lifetime by conventional spin precession measurements with magnetic fields perpendicular to the graphene plane. Then, to evaluate the out-of-plane spin lifetime, we implement spin precession measurements under oblique magnetic fields that generate an out-of-plane spin population. We find that the spin-lifetime anisotropy of graphene on silicon oxide is independent of carrier density and temperature down to 150 K, and much weaker than previously reported. Indeed, within the experimental uncertainty, the spin relaxation is isotropic. Altogether with the gate dependence of the spin lifetime, this indicates that the spin relaxation is driven by magnetic impurities or random spin-orbit or gauge fields., This research was partially supported by the European Research Council under Grant Agreement No. 308023 SPINBOUND, by the Spanish Ministry of Economy and Competitiveness, MINECO (under Contract No. MAT2013-46785-P and Severo Ochoa No. SEV-2013-0295), and by the Secretariat for Universities and Research, Knowledge Department of the Generalitat de Catalunya. M.V.C., J.F.S. and J.C. acknowledge support from the Ramón y Cajal, Juan de la Cierva and Beatriu de Pinós programs, respectively. F.B. acknowledges funding from the People Programme (Marie Curie Actions) of the European Union’s Seventh Framework Programme FP7/2007-2013/ under REA Grant Agreement No. 624897. J.E.S. and J.V.d.V. acknowledge funding from the Methusalem Funding of the Flemish Government and the Research Foundation-Flanders (FWO).

Using first-principles calculations, we investigate the electronic, mechanical, and optical properties of monolayer WTe2. Atomic structure and ground state properties of monolayer WTe2 (Td phase) are anisotropic which are in contrast to similar monolayer crystals of transition metal dichalcogenides, such as MoS2, WS2, MoSe2, WSe2, and MoTe2, which crystallize in the H-phase. We find that the Poisson ratio and the in-plane stiffness is direction dependent due to the symmetry breaking induced by the dimerization of the W atoms along one of the lattice directions of the compound. Since the semimetallic behavior of the Td phase originates from this W-W interaction (along the a crystallographic direction), tensile strain along the dimer direction leads to a semimetal to semiconductor transition after 1% strain. By solving the Bethe-Salpeter equation on top of single shot G0W0 calculations, we predict that the absorption spectrum of Td-WTe2 monolayer is strongly direction dependent and tunable by tensile strain., This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. was supported by a FWO Pegasus Long Marie Curie Fellowship. S.C. and A.R. acknowledge the financial support from the Marie Curie grant FP7-PEOPLE-2013-IEF Project No. 628876, European Research Council (ERC-2010-AdG-267374), Spanish grant (FIS2013-46159-C3-1-P), Grupos Consolidados (IT578-13), and AFOSR Grant No. FA2386-15-1-0006 AOARD 144088, H2020-NMP-2014 project MOSTOPHOS, GA No. SEP-210187476, and COST Action MP1306 (EUSpec). S.C. acknowledges the support from The Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 115F388.

Trabajo presentado al Vertical-Cavity Surface-Emitting Lasers XIX, celebrado en San Francisco, California (US) del 11 al 12 de febrero de 2015., We have measured the effect of the temperature on the polarization-resolved characteristics of a 1550-nm singletransverse mode vertical-cavity surface-emitting laser (VCSEL). Two double polarization switchings (PS) are observed. For low temperatures a PS from longer to shorter wavelengths (Type II PS) followed by the opposite PS (Type I) is observed. For higher temperatures Type I followed by Type II PS are measured. A simple expression relating the spin flip rateto the dichroism, differential gain, threshold current and PS current is derived. With this expression the dependence of the spin-flip rate on the temperature is obtained., This work has been funded by the Ministerio de Economía y Competitividad, Spain under project TEC2012-38864-C03-03 and cofinanced by FEDER funds. A. Quirce acknowledges FWO for her Post Doc fellowship and H. Thienpont and K. Panajotov are grateful to the Methusalem foundation for financial support.

Trabajo presentado a la Physics and Simulation of Optoelectronic Devices XXIII Conference, celebrada en San Francisco, California (US) del 9 a 12 de febrero de 2015., Chaotic Lidar systems (CLIDAR) are used for high-resolution ranging. They are based on the correlation of a chaotic signal waveform with the signal that is reflected back from the target. We report a novel CLIDAR system based on the autocorrelation of the signal obtained by the superposition of the chaotic signal waveform and the signal that is reflected from the target. A simplified set-up with just one detector is required in contrast to the two detectors used in standard CLIDAR systems. Our experimental results are obtained with a 1550-nm vertical-cavity surface-emitting laser (VCSEL) with chaotic dynamics due to optical feedback. Our CLIDAR system provides an autocorrelation function with several sharp minima. The position of the target is obtained from the location of those minima. A theoretical analysis of the CLIDAR system is also presented. A rate equation model for the polarization of a VCSEL subject to optical feedback is the basis for the simulation of the CLIDAR system. A comparison between our theoretical and experimental results is performed, resulting in a good agreement in the chaotic signal but in a different sign of the CLIDAR signal., This work has been funded by the Ministerio de Economía y Competitividad, Spain under project TEC2012-38864-C03-03 and cofinanced by FEDER funds. A. Quirce acknowledges FWO for her Post Doc fellowship and H. Thienpont and K. Panajotov are grateful to the Methusalem foundation for financial support.

We report on an experimental investigation of the nonlinear dynamics and the chaos synchronization in mutually coupled but nonidentical 1550-nm vertical-cavity surface-emitting lasers (VCSELs) subject to optical injection with parallel polarizations of the two lasers. We use an asymmetric all-fiber setup with a large total coupling delay time, 274.2 ns. The results are analyzed for different values of the relevant parameters, namely, the frequency detuning, that is, the emitting frequency difference between the two coupled VCSELs, and the coupling strength between the two lasers. We show that dynamics in the orthogonal linear polarization can appear for negative frequency detunings. A rich variety of nonlinear behaviors such as limit cycle, period doubling, and chaos have been observed. Moreover, achronal chaotic synchronization for an asymmetric setup and nonidentical VCSELs is found with a time shift corresponding to the large coupling delay time between the lasers. We analyze the leader-laggard relationship and the accuracy of the synchronization by the cross-correlation function., European Regional Development Fund (ERDF); Fonds Wetenschappelijk Onderzoek (FWO); Methusalem Foundation; Ministerio de Economía y Competitividad (MINECO) (TEC2012-38864-C03-03).