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Results for "Daniel R. P. Vieira"

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Gapless spectrum in a class of S=1 exchange models with long-range interactionsFeb 13 1997Sep 19 1997We present evidence for the absence of a gap in a class of S=1 antiferromagnetic exchange models. The spin exchange is long-ranged of the type $-(-1)^{i-j}/|i-j|^{\alpha}$ where $1<\alpha<3$. We have shown previously that without the alternating factor ... More
Spin dynamics of the S=1/2 antiferromagnetic zig-zag ladder with anisotropyJan 08 2002We use exact diagonalization and the modified Lanczos method to study the finite energy and finite momentum spectral weight of the longitudinal and transverse spin excitations of the anisotropic zig-zag ladder. We find that the spin excitations form continua ... More
Spinor Description of a General Spin-J SystemDec 13 2000We consider a spin coherent states description of a general quantum spin system. It is shown that it is possible to use the spin-1/2 representation to study the general spin-J case. We identify the 1/2 spinor components as the homogeneous coordinates ... More
Haldane gap in a S=1 exchange model with long-range interactionsFeb 13 1997The ground-state properties of the S=1 Haldane-Shastry model are studied using a modified Lanczos algorithm and diagonalizing exactly small chains. We find evidence that, as for the antiferromagnetic Heisenberg model, the spectrum shows a gap, in contrast ... More
Phenomenological model for the remanent magnetization of dilute quasi-one-dimensional antiferromagnetsApr 18 2002Oct 29 2002We present a phenomenological model for the remanent magnetization at low temperatures in the quasi-one-dimensional dilute antiferromagnets CH_{3}NH_{3}Mn_{1-x}Cd_{x} Cl_{3}\cdot 2H_{2}O and (CH_{3})_{2}NH_{2}Mn_{1-x}Cd_{x}Cl_{3}\cdot 2H_{2}O. The model ... More
Comparison of three different self-interaction corrections for an exactly solvable model systemJul 17 2008A systematic comparison of three approximate self-interaction corrections (SICs), Perdew-Zunger SIC, Lundin-Eriksson SIC and extended Fermi-Amaldi SIC, is performed for a model Hamiltonian whose exact many-body solution and exact local-density approximation ... More
Rate Constants for Fine-Structure Excitations in O-H Collisions with Error Bars Obtained by Machine LearningJan 08 2017We present an approach using a combination of coupled channel scattering calculations with a machine- learning technique based on Gaussian Process regression to determine the sensitivity of the rate constants for non-adiabatic transitions in inelastic ... More
Spin-density Wave in Ising-coupled Antiferromagnetic ChainsSep 13 1997The effect of anisotropy in the nearest-neighbor spin interactions that couple $N\geq 2$ consecutive spin-1/2 antiferromagnetic chains is studied theoretically by considering the limit where the coupling is purely of the Ising type. An analysis based ... More
Simple implementation of complex functionals: scaled selfconsistencyNov 17 2006We explore and compare three approximate schemes allowing simple implementation of complex density functionals by making use of selfconsistent implementation of simpler functionals: (i) post-LDA evaluation of complex functionals at the LDA densities (or ... More
Vector Field Neural NetworksMay 16 2019This work begins by establishing a mathematical formalization between different geometrical interpretations of Neural Networks, providing a first contribution. From this starting point, a new interpretation is explored, using the idea of implicit vector ... More
Versatile Hall magnetometer with variable sensitivity assembly for characterization of the magnetic properties of nanoparticlesMay 14 2019Jun 17 2019A Hall magnetometer with variable sensitivity is constructed to measure the magnetic properties of magnetic nanoparticles manufactured by different methods. This novel magnetometer can also be used to measure bulk materials and samples in liquids. The ... More
Phase diagrams of soluble multi-spin glass modelsMay 23 2005We include p-spin interactions in a spherical version of a soluble mean-field spin-glass model proposed by van Hemmen. Due to the simplicity of the solutions, which do not require the use of the replica trick, we are able to carry out a detailed investigation ... More
Correlated disordered interactions on Potts modelsJan 31 2002Using a weak-disorder scheme and real-space renormalization-group techniques, we obtain analytical results for the critical behavior of various q-state Potts models with correlated disordered exchange interactions along d1 of d spatial dimensions on hierarchical ... More
Versatile Hall magnetometer with variable sensitivity assembly for characterization of the magnetic properties of nanoparticlesMay 14 2019A Hall magnetometer with variable sensitivity is constructed to measure the magnetic properties of magnetic nanoparticles manufactured by different methods. This novel magnetometer can also be used to measure bulk materials and samples in liquids. The ... More
Magnetic impurities in a superconductor: Effect of domain walls and interferenceJun 02 2007We consider the effect of magnetic impurities, modeled by classical spins, in a conventional superconductor. We study their effect on the quasiparticles, specifically on the spin density and local density of states (LDOS). As previously emphasized, the ... More
Non-equilibrium properties of the S=1/2 Heisenberg model in a time-dependent magnetic fieldMay 07 2003The time-dependent behavior of the Heisenberg model in contact with a phonon heat bath and in an external time-dependent magnetic field is studied by means of a path integral approach. The action of the phonon heat bath is taken into account up to the ... More
Fidelity spectrum and phase transitions of quantum systemsJul 29 2011Quantum fidelity between two density matrices, $F(\rho_1,\rho_2)$ is usually defined as the trace of the operator ${\cal F}=\sqrt{\sqrt{\rho_1} \rho_2 \sqrt{\rho_1}}$. We study the logarithmic spectrum of this operator, which we denote by {\it fidelity ... More
Lattice statistical models for the nematic transitions in liquid-crystalline systemsAug 29 2016We investigate the connections between some simple Maier-Saupe lattice models, with a discrete choice of orientations of the microscopic directors, and a recent proposal of a two-tensor formalism to describe the phase diagrams of nematic liquid-crystalline ... More
Phase diagram of a model for a binary mixture of nematic molecules on a Bethe latticeSep 14 2010We investigate the phase diagram of a discrete version of the Maier-Saupe model with the inclusion of additional degrees of freedom to mimic a distribution of rodlike and disklike molecules. Solutions of this problem on a Bethe lattice come from the analysis ... More
Phase diagram of a random-anisotropy mixed-spin Ising modelFeb 19 2001We investigate the phase diagram of a mixed spin-1/2--spin-1 Ising system in the presence of quenched disordered anisotropy. We carry out a mean-field and a standard self-consistent Bethe--Peierls calculation. Depending on the amount of disorder, there ... More
Constraining the physics of the early UniverseMar 26 2019The established cosmological theory which describes the history of the Universe since shortly after the "Big Bang" until today is remarkably successful. Thanks to the increasing precision of available observational data, we are now able to considerably ... More
Low-energy properties of aperiodic quantum spin chainsMar 25 2004Feb 24 2005We investigate the low-energy properties of antiferromagnetic quantum XXZ spin chains with couplings following two-letter aperiodic sequences, by an adaptation of the Ma-Dasgupta-Hu renormalization-group method. For a given aperiodic sequence, we argue ... More
Factorization of the Non-Stationary Schrodinger OperatorApr 18 2007Jun 15 2007We consider a factorization of the non-stationary Schrodinger operator based on the parabolic Dirac operator introduced by Cerejeiras/ Kahler/ Sommen. Based on the fundamental solution for the parabolic Dirac operators, we shall construct appropriated ... More
Solution of Supplee's submarine paradox through special and general relativityNov 23 2016In 1989 Supplee described an apparent relativistic paradox on which a submarine seems to sink in a given frame while floating in another one. If the submarine density is adjusted to be the same as the water density (when both of them are at rest) and ... More
Lorentz-Violating QCD Corrections to Deep Inelastic ScatteringOct 28 2016In this work, we present CPT- and Lorentz-violating corrections to observable quantities in electron-proton scattering. We also show how the theoretical prediction can be used together with data to establish bounds on a coefficient for CPT and Lorentz ... More
On the number of roots of self-inversive polynomials on the complex unit circleFeb 18 2015Jul 03 2016We present a sufficient condition for a self-inversive polynomial to have a fixed number of roots on the complex unit circle. We also prove that these roots are simple when that condition is satisfied. This generalizes the condition found by Lakatos and ... More
Pioneer Anomaly and the Kuiper Belt mass distributionJun 15 2005Jun 18 2006Pioneer 10 and 11 were the first probes sent to study the outer planets of the Solar System and Pioneer 10 was the first spacecraft to leave the Solar System. Besides their already epic journeys, Pioneer 10 and 11 spacecraft were subjected to an unaccounted ... More
Polynomials with symmetric zerosApr 01 2019Polynomials whose zeros are symmetric either to the real line or to the unit circle are very important in mathematics and physics. We can classify them into three main classes: the self-conjugate polynomials, whose zeros are symmetric to the real line; ... More
Fifteen-vertex models with non-symmetric $R$ matricesAug 19 2019In this work, we employ the algebraic-differential method recently developed by the author to solve the Yang-Baxter equation for arbitrary fifteen-vertex models satisfying the ice-rule. We show that there are four different families of such regular $R$ ... More
Friedel oscillations in one-dimensional metals: from Luttinger's theorem to the Luttinger liquidOct 01 2007Charge density and magnetization density profiles of one-dimensional metals are investigated by two complementary many-body methods: numerically exact (Lanczos) diagonalization, and the Bethe-Ansatz local-density approximation with and without a simple ... More
How to count the number of zeros that a polynomial has on the unit circle?Feb 12 2019The classical problem of counting the number of real zeros of a real polynomial was solved a long time ago by Sturm. The analogous problem of counting the number of zeros that a polynomial has on the unit circle is, however, still an open problem. In ... More
Aperiodic quantum XXZ chains: Renormalization-group resultsOct 28 2004Apr 24 2005We report a comprehensive investigation of the low-energy properties of antiferromagnetic quantum XXZ spin chains with aperiodic couplings. We use an adaptation of the Ma-Dasgupta-Hu renormalization-group method to obtain analytical and numerical results ... More
Solving and classifying the solutions of the Yang-Baxter equation through a differential approach. Two-state systemsDec 05 2017Oct 18 2018The formal derivatives of the Yang-Baxter equation with respect to its spectral parameters, evaluated at some fixed point of these parameters, provide us with two systems of differential equations. The derivatives of the $R$ matrix elements, however, ... More
Fundamental Solutions of the Instationary Schrodinger Difference OperatorNov 23 2007In this paper we will study the existence of fundamental solutions for the explicit and implicit backward time dependent Schodinger equation, via discrete Fourier transform and its symbol for the Laplace operator. In both cases we will prove that the ... More
Non-damping magnetization oscillations in a single-domain ferromagnetOct 11 2005Non-damped oscillations of the magnetization vector of a ferromagnetic system subject to a spin polarized current and an external magnetic field are studied theoretically by solving the Landau-Lifshitz-Gilbert equation. It is shown that the frequency ... More
GPIC - GPU Power Iteration ClusterApr 10 2016This work presents a new clustering algorithm, the GPIC, a Graphics Processing Unit (GPU) accelerated algorithm for Power Iteration Clustering (PIC). Our algorithm is based on the original PIC proposal, adapted to take advantage of the GPU architecture, ... More
Fidelity Between Partial States as Signature of Quantum Phase TransitionsAug 26 2007We introduce a partial state fidelity approach to quantum phase transitions. We consider a superconducting lattice with a magnetic impurity inserted at its centre, and look at the fidelity between partial (either one-site or two-site) quantum states. ... More
Entanglement signatures of the quantum phase transition induced by a magnetic impurity in a superconductorJun 11 2007The insertion of a magnetic impurity in a superconductor induces a first order quantum phase transition as the coupling to the electronic spin density increases. As the transition is crossed, a discontinuity is exhibited by various quantities, like the ... More
Decoupling of the S=1/2 antiferromagnetic zig-zag ladder with anisotropyApr 05 2001The spin-1/2 antiferromagnetic zig-zag ladder is studied by exact diagonalization of small systems in the regime of weak inter-chain coupling. A gapless phase with quasi long-range spiral correlations has been predicted to occur in this regime if easy-plane ... More
Superconductivity in the SU(N) Anderson Lattice at U=\inftyJul 10 2000Jul 11 2000We present a mean-field study of superconductivity in a generalized N-channel cubic Anderson lattice at U=\infty taking into account the effect of a nearest-neighbor attraction J. The condition U=\infty is implemented within the slave-boson formalism ... More
The slimming effect of advection on black-hole accretion flowsOct 30 2015Jun 20 2016At super-Eddington rates accretion flows onto black holes have been described as slim (aspect ratio $H/R \lesssim 1$) or thick (H/R >1) discs, also known as tori or (Polish) doughnuts. The relation between the two descriptions has never been established, ... More
Fractal analysis of weld defect patterns obtained by radiographic testsDec 18 2006This paper presents a fractal analysis of radiographic patterns obtained from specimens with three types of inserted welding defects: lack of fusion, lack of penetration, and porosity. The study focused on patterns of carbon steel beads from radiographs ... More
Guises and Disguises of Quadratic DivergencesOct 04 2014In this contribution, we present a new perspective on the control of quadratic divergences in quantum field theory, in general, and in the Higgs naturalness problem, in particular. Our discussion is essentially based on an approach where UV divergences ... More
Physical signatures of discontinuities of the time-dependent exchange-correlation potentialFeb 06 2009The exact exchange-correlation (XC) potential in time-dependent density-functional theory (TDDFT) is known to develop steps and discontinuities upon change of the particle number in spatially confined regions or isolated subsystems. We demonstrate that ... More
Simple parametrization for the ground-state energy of the infinite Hubbard chain incorporating Mott physics, spin-dependent phenomena and spatial inhomogeneityFeb 24 2011Jun 20 2012Simple analytical parametrizations for the ground-state energy of the one-dimensional repulsive Hubbard model are developed. The charge-dependence of the energy is parametrized using exact results extracted from the Bethe-Ansatz. The resulting parametrization ... More
On the Stability of the Satellites of Asteroid 87 SylviaFeb 12 2009he triple asteroidal system (87) Sylvia is composed of a 280-km primary and two small moonlets named Romulus and Remus (Marchis et al 2005). Sylvia is located in the main asteroid belt. The satellites are in nearly equatorial circular orbits around the ... More
Phase transitions in the majority-vote model with two types of noisesNov 16 2015Jan 06 2016In this work we study the majority-vote model with the presence of two distinc noises. The first one is the usual noise $q$, that represents the probability that a given agent follows the minority opinion of his/her social contacts. On the other hand, ... More
Anomalous Hall effect in superconductors with spin-orbit interactionNov 29 2011We calculate the anomalous Hall conductance of superconductors with spin-orbit interaction and with either uniform or local magnetization. In the first case we consider a uniform ferromagnetic ordering in a spin triplet superconductor, while in the second ... More
Maier-Saupe model for a mixture of uniaxial and biaxial moleculesJul 14 2015We introduce shape fluctuations in a liquid-crystalline system by considering an elementary Maier--Saupe lattice model for a mixture of uniaxial and biaxial molecules. Shape variables are treated in the annealed (thermalized) limit. We analyze the thermodynamic ... More
Conductance behavior with temperature and magnetic field in the disordered films of titanium nitrideFeb 03 2014We report in this paper the temperature and mangetic field dependence of the conductance in the polycrystalline film of titanium nitride, before and after heating at ambient conditions. The difference between the two films is the room temperature sheet ... More
Local electronic properties in the superconducting and the normal phase in the disordered film of titanium nitrideJan 19 2014We present in this paper the conductance maps at 100 mK in the disordered polycrystalline film of titanium nitride (TiN). At 5 nm, the film is close to quasi-two dimensional limit and exhibits features pertaining to the superconductor to insulator transition. ... More
Crossover from one- to three-dimensional behavior in the S = 1/2 Heisenberg antiferromagnet Cu(N2H5)2(SO4)2Jul 07 2016Sep 13 2016From experimental and theoretical analyses of magnetic and specific-heat properties, we present the complete magnetic phase diagram of the quasi-one-dimensional antiferromagnet Cu(N$_2$H$_5$)$_2$(SO$_4$)$_2$. On cooling and at zero magnetic field this ... More
The N=1 effective actions of D-branes in Type IIA and IIB orientifoldsApr 12 2011Jun 21 2011We discuss the four-dimensional N=1 effective actions of single space-time filling Dp-branes in general Type IIA and Type IIB Calabi-Yau orientifold compactifications. The effective actions depend on an infinite number of normal deformations and gauge ... More
The algebra of bounded type holomorphic functions on the ballNov 09 2018We study the spectrum $M_b(U)$ of the algebra of bounded type holomorphic functions on a complete Reinhardt domain in a symmetrically regular Banach space $E$ as an analytic manifold over the bidual of the space. In the case that $U$ is the unit ball ... More
Conditions for the onset of the current filamentation instability in the laboratorySep 27 2017Sep 29 2017Current Filamentation Instability (CFI) is capable of generating strong magnetic fields relevant to explain radiation processes in astrophysical objects and lead to the onset of particle acceleration in collisionless shocks. Probing such extreme scenarios ... More
Arbitrariness in the gravitational Chern-Simons-like term induced radiativelyMar 11 2014Jun 18 2014Lorentz violation through a radiatively induced Chern-Simons-like term in a fermionic theory embedded in linearized quantum gravity with a Lorentz- and CPT-violating axial-vector term in the fermionic sector proportional to a constant field $b_\mu$ has ... More
Non-Markovian effects in electronic and spin transportDec 29 2014We derive a non-Markovian master equation for the evolution of a class of open quantum systems consisting of quadratic fermionic models coupled to wide-band reservoirs. This is done by providing an explicit correspondence between master equations and ... More
Noise-induced absorbing phase transition in a model of opinion formationJun 13 2016In this work we study a 3-state ($+1$, $-1$, $0$) opinion model in the presence of noise and disorder. We consider pairwise competitive interactions, with a fraction $p$ of those interactions being negative (disorder). Moreover, there is a noise $q$ that ... More
Threshold $q$-voter modelJul 10 2018We introduce the threshold $q$-voter opinion dynamics where an agent, facing a binary choice, can change its mind when at least $q_0$ amongst $q$ neighbors share the opposite opinion. Otherwise, the agent can still change its mind with a certain probability ... More
Fabrication of antenna-coupled KID array for Cosmic Microwave Background detectionOct 30 2017Kinetic Inductance Detectors (KIDs) have become an attractive alternative to traditional bolometers in the sub-mm and mm observing community due to their innate frequency multiplexing capabilities and simple lithographic processes. These advantages make ... More
Disorder driven inhomogeneous phase in the 2D-superconducting film of titanium nitrideFeb 13 2014Aug 18 2015Typically the superconducting phase weakens at several points with the increase in disorder before it is distroyed in the 2d-thin films. This may lead to an inhomogeneous superconducting state without a continuous phase. Here we present scanning tunneling ... More
Orthogonal polynomials and Möbius transformationsApr 15 2019Given an orthogonal polynomial sequence on the real line, another sequence of polynomials can be found by composing these polynomials with a general M\"obius transformation. In this work, we study the properties of such M\"obius-transformed polynomials. ... More
Thermally activated in-plane magnetization rotation induced by spin torqueNov 13 2013We study the role of thermal fluctuations on the spin dynamics of a thin permalloy film with a focus on the behavior of spin torque and find that the thermally assisted spin torque results in new aspects of the magnetization dynamics. In particular, we ... More
A Method for Individual Source Brightness Estimation in Single- and Multi-band DataDec 11 2009Nov 09 2010We present a method of reliably extracting the flux of individual sources from sky maps in the presence of noise and a source population in which number counts are a steeply falling function of flux. The method is an extension of a standard Bayesian procedure ... More
Phase diagram of random lattice gases in the annealed limitSep 02 1998Oct 14 1998An analysis of the random lattice gas in the annealed limit is presented. The statistical mechanics of disordered lattice systems is briefly reviewed. For the case of the lattice gas with an arbitrary uniform interaction potential and random short-range ... More
One-dimensional Ising model with long-range and random short-range interactionsSep 02 1998The one-dimensional Ising model in an external magnetic field with uniform long-range interactions and random short-range interactions satisfying bimodal annealed distributions is studied. This generalizes the random model discussed by Paladin et al. ... More
Emergent dimerization and localization in disordered quantum chainsApr 13 2018Sep 14 2018We uncover a novel mechanism for inducing a gapful phase in interacting many-body quantum chains. The mechanism is nonperturbative, being triggered only in the presence of both strong interactions and strong aperiodic (disordered) modulation. In the context ... More
Numerical Clifford Analysis for Nonlinear Schrodinger ProblemJun 04 2007Dec 04 2007The aim of this work is to study the numerical solution of the nonlinear Schrodinger problem using a combination between Witt basis and finite difference approximations. We construct a discrete fundamental solution for the non-stationary Schrodinger operator ... More
Optimization of supply diversity for the self-assembly of simple objects in two and three dimensionsOct 03 2007Oct 04 2007The field of algorithmic self-assembly is concerned with the design and analysis of self-assembly systems from a computational perspective, that is, from the perspective of mathematical problems whose study may give insight into the natural processes ... More
Renormalization group approach for Lorentz-violating scalar field theory at all loop ordersFeb 05 2015Oct 14 2015We compute, both explicitly up to next-to-leading order and in a proof by induction for all loop levels, the critical exponents for thermal Lorentz-violating O($N$) self-interacting scalar field theory. They are evaluated in a massless theory renormalized ... More
Consequences of nonconformist behaviors in a continuous opinion modelJan 18 2016We investigate opinion formation in a kinetic exchange opinion model, where opinions are represented by numbers in the real interval $[-1,1]$ and agents are typified by the individual degree of conviction about the opinion that they support. Opinions ... More
Boundary Algebraic Bethe Ansatz for a nineteen vertex model with $U_{q}[\mathrm{osp}(2|2)^{(2)}] symmetry$May 24 2017The boundary algebraic Bethe Ansatz for a supersymmetric nineteen vertex-model constructed from a three-dimensional representation of the twisted quantum affine Lie superalgebra $U_{q}[\mathrm{osp}(2|2)^{(2)}]$ is presented. The eigenvalues and eigenvectors ... More
Supercurrent induced domain wall motionNov 29 2011We study the dynamics of a magnetic domain wall, inserted in, or juxtaposed to, a conventional superconductor, via the passage of a spin polarized current through a FSF junction. Solving the Landau-Lifshitz-Gilbert equation of motion for the magnetic ... More
High orbital angular momentum harmonic generationNov 10 2016We identify and explore a high orbital angular momentum (OAM) harmonics generation and amplification mechanism that manipulates the OAM independently of any other laser property, by preserving the initial laser wavelength, through stimulated Raman backscattering ... More
Effect of Transverse Magnetic Field on Dynamics of Current Driven Domain Wall Motion in the Presence of Spin-Hall EffectMay 20 2015Theoretically, we study the dynamics of a current induced domain wall in the bi-layer structure consists of a ferromagnetic layer and a non-magnetic metal layer with strong spin-orbit coupling in the presence of spin-Hall effect. The analytical expressions ... More
The quadratic isoperimetric inequality for mapping tori of free group automorphisms I: Positive automorphismsNov 29 2002Jul 28 2005If $F$ is a finitely generated free group and $\phi$ is a positive automorphism of $F$ then $F\rtimes_\phi Z$ satisfies a quadratic isoperimetric inequality.
Detecting and modelling delayed density-dependence in abundance time series of a small mammal (Didelphis aurita)Feb 16 2017We study the population size time series of a Neotropical small mammal with the intent of detecting and modelling population regulation processes generated by density-dependent factors and their possible delayed effects. The application of analysis tools ... More
Chaos and Rotating Black Holes with HalosDec 01 1997The occurrence of chaos for test particles moving around a slowly rotating black hole with a dipolar halo is studied using Poincar\'e sections. We find a novel effect, particles with angular momentum opposite to the black hole rotation have larger chaotic ... More
Impact of Current on Static and Kinetic Depinning Fields of Domain Wall in Ferromagnetic NanostripMar 16 2015The impact of current on static and kinetic depinning fields of a domain wall in an one dimensional ferromagnetic nanostrip is investigated by solving the Landau-Lifshitz-Gilbert equation with adiabatic and non-adiabatic spin-transfer torques analytically ... More
Angular dependences in electroweak semi-inclusive leptoproductionJul 26 1999We present the leading order unpolarized and polarized cross sections in electroweak semi-inclusive deep inelastic leptoproduction. The azimuthal dependences in the cross section differential in the transverse momentum of the vector boson arise due to ... More
Amplification and generation of ultra-intense twisted laser pulses via stimulated Raman scatteringMar 09 2016Twisted Laguerre-Gaussian lasers, with orbital angular momentum and characterised by doughnut shaped intensity profiles, provide a transformative set of tools and research directions in a growing range of fields and applications, from super-resolution ... More
Reflection matrices with $U_q[osp^{(2)}(2|2m)]$ symmetryAug 17 2016Sep 14 2016In this work we report and classify the reflection $K$ matrices with the $U_{q}\left[\mathfrak{osp}^{(2)}\left(2|2m\right)\right]$ symmetry. This vertex model is the fermionic analogue of the Jimbo (bosonic) $U_{q}\left[D_{n+1}^{(2)}\right]$ vertex model. ... More
Covariant theory of gravitation in the framework of special relativityJul 12 2016Nov 06 2016Purely from covariance requirements regarding the special theory of relativity, we show that a moving body necessarily generates a gravitational magnetic field. Then, from the Lorentz transformations, we deduce the exact formul{\ae} describing these gravitomagnetic ... More
Covariant theory of gravitation in the framework of special relativityJul 12 2016Apr 28 2018In this work, we study the magnetic effects of gravity in the framework of special relativity. Imposing covariance of the gravitational force with respect to the Lorentz transformations, we show from a thought experiment that a magnetic-like force must ... More
Dynamics of Current and Field Driven Domain Wall Motion under the Influence of Transverse Magnetic FieldMar 16 2015Mar 18 2015The dynamics of transverse Neel domain wall in a ferromagnetic nanostrip in the presence of driving field, current and transverse magnetic field is investigated by the Landau-Lifshitz-Gilbert(LLG) equation with the adiabatic and non-adiabatic spin-transfer ... More
The sensitivity of a radical pair compass magnetoreceptor can be significantly amplified by radical scavengersJun 14 2017Sep 15 2017Birds have a remarkable ability to obtain navigational information from the Earth's magnetic field. The primary detection mechanism of this compass sense is uncertain but appears to involve the quantum spin dynamics of radical pairs formed transiently ... More
Source structure and molecular gas properties from high-resolution CO imaging of SPT-selected dusty star-forming galaxiesJan 29 2019We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of high-J CO lines ($J_\mathrm{up}=6$, 7, 8) and associated dust continuum towards five strongly lensed, dusty, star-forming galaxies (DSFGs) at redshift $z = 2.7$-5.7. These ... More
Chaos in black holes surrounded by gravitational wavesJun 10 1997The occurrence of chaos for test particles moving around Schwarzschild black holes perturbed by a special class of gravitational waves is studied in the context of the Melnikov method. The explicit integration of the equations of motion for the homoclinic ... More
Hosing Instability Suppression in Self-Modulated Plasma WakefieldsApr 22 2014We show that the hosing instability can be suppressed after the saturation of the self-modulation instability of a long particle bunch if the plasma density perturbation is linear. We derive scalings for maximum bunch tilts and seeds for the self-modulation ... More
Signatures of the self-modulation instability of relativistic proton bunches in the AWAKE experimentMar 05 2018We investigate numerically the detection of the self-modulation instability in a virtual detector located downstream from the plasma in the context of AWAKE. We show that the density structures, appearing in the temporally resolving virtual detector, ... More
Current-induced motion of a domain wall in magnetic nanowiresSep 22 2005The dynamics of current-induced motion of a magnetic domain wall in a quasi-one-dimensional ferromagnet with both easy-axis and easy-plane anisotropy, is studied. We pay a special attention to the case of a sharp domain wall, and calculate the spin torque ... More
Spatially Resolved [CII] Emission in SPT0346-52: A Hyper-Starburst Galaxy Merger at z~5.7Nov 19 2018SPT0346-52 is one of the most most luminous and intensely star-forming galaxies in the universe, with L_FIR > 10^13 L_sol and Sigma_SFR ~ 4200 M_sol yr^-1 kpc^-2. In this paper, we present ~0.15'' ALMA observations of the [CII]158micron emission line ... More
Where are the roots of the Bethe Ansatz equations?Feb 18 2015Jul 13 2015Changing the variables in the Bethe Ansatz Equations (BAE) for the XXZ six-vertex model we had obtained a coupled system of polynomial equations. This provided a direct link between the BAE deduced from the Algebraic Bethe Ansatz (ABA) and the BAE arising ... More
Lorentz violation and deep inelastic scatteringOct 27 2016Apr 07 2017The effects of quark-sector Lorentz violation on deep inelastic electron-proton scattering are studied. We show that existing data can be used to establish first constraints on numerous coefficients for Lorentz violation in the quark sector at an estimated ... More
On the Associativity of Infinite Matrix MultiplicationMar 26 2018Mar 28 2018A natural definition of the product of infinite matrices mimics the usual formulation of multiplication of finite matrices with the caveat (in the absence of any sense of convergence) that the intersection of the support of each row of the first factor ... More
Vector Field Based Neural NetworksFeb 22 2018A novel Neural Network architecture is proposed using the mathematically and physically rich idea of vector fields as hidden layers to perform nonlinear transformations in the data. The data points are interpreted as particles moving along a flow defined ... More
Reflection $K$-matrices for a nineteen vertex model with $U_{q}[\mathrm{osp}\left(2|2\right)^{\left(2\right)}]$ symmetryMar 06 2017We derive the solutions of the boundary Yang-Baxter equation associated with a supersymmetric nineteen vertex model constructed from the three-dimensional representation of the twisted quantum affine Lie superalgebra $U_{q}[\mathrm{osp}\left(2|2\right)^{\left(2\right)}]\simeq ... More
Hardened Paxos Through Consistency ValidationOct 20 2017Oct 25 2017Due to the emergent adoption of distributed systems when building applications, demand for reliability and availability has increased. These properties can be achieved through replication techniques using middleware algorithms that must be capable of ... More
Graphene field-effect transistor array with integrated electrolytic gates scaled to 200 mmJan 07 2016Ten years have passed since the beginning of graphene research. In this period we have witnessed breakthroughs both in fundamental and applied research. However, the development of graphene devices for mass production has not yet reached the same level ... More
Chaos and Taub-NUT related spacetimesDec 05 1997The occurrence of chaos for test particles moving in a Taub-NUT spacetime with a dipolar halo perturbation is studied using Poincar\'e sections. We find that the NUT parameter (magnetic mass) attenuates the presence of chaos.