• Small amplitude oscillations of sine-gordon vortex states in planar magnets in three dimensions 

  Pereira, A . R. (Brazilian Journal of Physics, 2002-09)

  We investigate the spectrum of small amplitude oscillations of the sine-Gordon vortex-antivortex pair in layered ferromagnetic systems described by the anisotropic three-dimensional XY-model. In the case of a small interlayer ...
• Investigation of large enhancement of spin hall angle in heterostructures of Ag nanoparticles randomly grown in Pt 

  Santos, O. A.; Silva, E. F.; Gamino, M.; Mendes, J. B. S.; Rezende, S. M.; Azevedo, A. (AIP Advances, 2019)

  The spin Hall angle (SHA) represents the efficiency of the conversion between spin current into charge current and vice-versa. In this paper, we report the experimental detection of large enhancement of the effective SHA ...
• Robustness and fragility of the susceptible- infected- susceptible epidemic models on complex networks 

  Cota, Wesley; Mata, Angélica S.; Ferreira, Silvio C. (Physical Review E, 2018)

  We analyze two alterations of the standard susceptible-infected-susceptible (SIS) dynamics that preserve the central properties of spontaneous healing and infection capacity of a vertex increasing unlimitedly with its ...
• Griffiths phases in infinite- dimensional, non- hierarchical modular networks 

  Cota, Wesley; Ódor, Géza; Ferreira, Silvio C. (Scientific Reports, 2018)

  Griffiths phases (GPs), generated by the heterogeneities on modular networks, have recently been suggested to provide a mechanism, rid of fine parameter tuning, to explain the critical behavior of complex systems. One ...
• Local roughness exponent in the nonlinear molecular-beam-epitaxy universality class in one dimension 

  Ferreira, Silvio C.; Luis, Edwin E. Mozo; Assis, Thiago A. de; Andrade, Roberto F. S. (Physical Review, 2019-02)

  We report local roughness exponents, αloc, for three interface growth models in one dimension which are believed to belong to the nonlinear molecular-beam-epitaxy (nMBE) universality class represented by the Villain-Lais-Das ...
• Eden model with nonlocal growth rules and kinetic roughening in biological systems 

  Ferreira, Silvio C.; Santalla, Silvia N. (Physical Review, 2018-08)

  We investigate an off-lattice Eden model where the growth of new cells is performed with a probability dependent on the availability of resources coming externally towards the growing aggregate. The concentration of nutrients ...
• Effects of post-lithography cleaning on the yield and performance of CVD graphene-based devices 

  Araujo, Eduardo Nery Duarte de; Sousa, Thiago Alonso Stephan Lacerda de; Guimarães, Luciano de Moura; Plentz, Flavio (Beilstein Journal of Nanotechnology, 2019)

  The large-scale production of high-quality and clean graphene devices, aiming at technological applications, has been a great challenge over the last decade. This is due to the high affinity of graphene with polymers that ...
• Collapse transition in polymer models with multiple monomers per site and multiple bonds per edge 

  Rodrigues, Nathann T.; Oliveira, Tiago J. (Physical Review E, 2017-12)

  We present results from extensive Monte Carlo simulations of polymer models where each lattice site can be visited by up to K monomers and no restriction is imposed on the number of bonds on each lattice edge. These multiple ...
• Kardar- Parisi- Zhang growth on one- dimensional decreasing substrates 

  Carrasco, I. S. S.; Oliveira, T. J. (Physical Review E, 2018-07)

  Recent experimental works on one-dimensional (1D) circular Kardar-Parisi-Zhang (KPZ) systems whose radii decrease in time have reported controversial conclusions about the statistics of their interfaces. Motivated by this, ...
• Activation thresholds in epidemic spreading with motile infectious agents on scale-free networks 

  Silva, Diogo H.; Ferreira, Silvio C. (Chaos: An Interdisciplinary Journal of Nonlinear Science, 2018)

  We investigate a fermionic susceptible-infected-susceptible model with the mobility of infected individuals on uncorrelated scale-free networks with power-law degree distributions P(k)∼k−γP(k)∼k−γ of exponents 2<γ<32<γ<3. ...
• Effects of caffeine on the structure and conformation of DNA: A force spectroscopy study 

  Moura, T. A.; Oliveira, L.; Rocha, M.S. (International Journal of Biological Macromolecules, 2019-06-01)

  Here, we use single molecule force spectroscopy performed with optical tweezers in order to investigate the interaction between Caffeine and the DNA molecule for various different concentrations of the alkaloid and under ...
• Mathematical modeling of dengue epidemic: control methods and vaccination strategies 

  Carvalho, Sylvestre Aureliano; Silva, Stella Olivia da; Charret, Iraziet da Cunha (Theory in Biosciences, 2018-04)

  Dengue is, in terms of death and economic cost, one of the most important infectious diseases in the world. So, its mathematical modeling can be a valuable tool to help us to understand the dynamics of the disease and to ...
• Loop quantization of a model for D = 1 + 2 (anti)de sitter gravity coupled to topological matter 

  Oporto, Zui; Constantinidis, Clisthenis P.; Piguet, Olivier (Classical and Quantum Gravity, 2015)

  We present a complete quantization of Lorentzian D = 1 + 2 gravity with cosmological constant, coupled to a set of topological matter fields. The approach of loop quantum gravity is used thanks to a partial gauge fixing ...
• Polymers with nearest- and next nearest-neighbor interactions on the Husimi lattice 

  Oliveira, Tiago J. (Journal of Physics A: Mathematical and Theoretical, 2016)

  The exact grand-canonical solution of a generalized interacting self-avoid walk (ISAW) model, placed on a Husimi lattice built with squares, is presented. In this model, beyond the traditional interaction ω1=eϵ1/kBT between ...
• In-place bonded semiconductor membranes as compliant substrates for III–V compound devices 

  Rodrigues, Leonarde N.; Silva, Saimon Filipe Covre da; Garcia Jr., Ailton J.; Morelhão, Sergio L.; Couto Jr, Odilon D. D.; Iikawa, Fernando (Nanoscale, 2019)

  Overcoming the critical thickness limit in pseudomorphic growth of lattice mismatched heterostructures is a fundamental challenge in heteroepitaxy. On-demand transfer of light-emitting structures to arbitrary host substrates ...
• Experimental and theoretical evidences for the ice regime in planar artificial spin ices 

  Loreto, R. P.; Gonçalves, R. S.; Pereira, A. R.; Araujo, C. I. L. de; Nascimento, F. S.; Borme, J.; Cezar, J. C.; Nisoli, C. (Journal of Physics: Condensed Matter, 2019)

  In this work, we explore a kind of geometrical effect in the thermodynamics of artificial spin ices (ASI). In general, such artificial materials are athermal. Here, We demonstrate that geometrically driven dynamics in ASI ...
• Skyrmions and merons in two-dimensional antiferromagnetic systems 

  Fernandes, R. L.; Lopes., R. J. C; Pereira, A. R (Solid State Communications, 2019-03)

  We have investigated (numerically) skyrmions constituted by two merons in two-dimensional Heisenberg antiferromagnets. The behavior and stability of these topological pseudo-particles are analyzed in discrete and finite ...
• Monte Carlo simulations of polymers with nearest- and next nearest-neighbor interactions on square and cubic lattices 

  Rodrigues, Nathann T; Oliveira, Tiago J (Journal of Physics A: Mathematical and Theoretical, 2014)

  We study a generalized interacting self-avoiding walk (ISAW) model with nearest- and next nearest-neighbor (NN and NNN) interactions on square and cubic lattices. In both dimensions, the phase diagrams show coil and globule ...
• On coherent states and the Self-Consistent Harmonic Approximation 

  Moura, A. R.; Lopes, R. J. C. (Journal of Magnetism and Magnetic Materials, 2019-02-15)

  We used the Self-Consistent Harmonic Approximation (SCHA) to study the thermodynamics of the precession magnetization in a two-dimensional isotropic ferromagnet. The SCHA treats the Hamiltonian in terms of the canonically ...
• Berry phases and zero-modes in toroidal topological insulator 

  Fonseca, Jakson M.; Moura-Melo, Winder A.; Pereira, Afranio R.; Carvalho-Santos, Vagson L. (The European Physical Journal B, 2016-06)

  An effective Hamiltonian describing the surface states of a toroidal topological insulator is obtained, and it is shown to support both bound-states and charged zero-modes. Actually, the spin connection induced by the ...

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