Search Results - "MOURA, W. A"

Surface states and breaking down of spin-to-surface locking on a conical topological insulator quantum dot by Veiga, L. G., Moura-Melo, W. A.

“…We study a conical topological insulator quantum dot and we show how the cone tip affects the surface states energy spectrum. This is obtained by analytically…”
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From confinement to deconfinement of magnetic monopoles in artificial rectangular spin ices by Nascimento, F S, Mól, L A S, Moura-Melo, W A, Pereira, A R

“…We study a frustrated two-dimensional array of dipoles forming an artificial rectangular spin ice with horizontal and vertical lattice parameters given by a…”
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Dynamics and hysteresis in square lattice artificial spin ice by Wysin, G M, Moura-Melo, W A, Mól, L A S, Pereira, A R

“…Dynamical effects under geometrical frustration are considered in a model for artificial spin ice on a square lattice in two dimensions. Each island of the…”
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Magnetic monopole free motion in two-dimensional artificial spin ice by Duarte, D. G., de Oliveira, L. B., Nascimento, F. S., Moura-Melo, W. A., Pereira, A. R., de Araujo, C. I. L.

“…Magnetic monopole motion (without its partner in a pair) as a function of external magnetic fields is presented as a fingerprint of freedom of these emergent…”
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Discrete double core skyrmions in magnetic thin films by Amaral, M.A., Silva, R.L., Pereira, A.R., Moura-Melo, W.A.

“…We study the Belavin–Polyakov double core skyrmions in two-dimensional isotropic Heisenberg ferromagnets on a discrete square lattice by means of spin dynamic…”
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Impedance spectroscopy study of dehydrated chitosan and chitosan containing LiClO4 by COSTA, M. M, TEREZO, A. J, MATOS, A. L, MOURA, W. A, GIACOMETTI, José A, SOMBRA, A. S. B

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Germanium microparticles as optically induced oscillators in optical tweezers by Campos, W. H., Moura, T. A., Marques, O. J. B. J., Fonseca, J. M., Moura-Melo, W. A., Rocha, M. S., Mendes, J. B. S.

“…Oscillatory dynamics is a key tool in optical tweezer applications. It is usually implemented by mechanical interventions that cannot be optically controlled…”
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Thermodynamics of elementary excitations in artificial magnetic square ice by Silva, R C, Nascimento, F S, Mól, L A S, Moura-Melo, W A, Pereira, A R

“…We investigate the thermodynamics of artificial square spin ice systems assuming only dipolar interactions among the islands that compose the array. Emphasis…”
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Realization of Rectangular Artificial Spin Ice and Direct Observation of High Energy Topology by Ribeiro, I. R. B., Nascimento, F. S., Ferreira, S. O., Moura-Melo, W. A., Costa, C. A. R., Borme, J., Freitas, P. P., Wysin, G. M., de Araujo, C. I. L., Pereira, A. R.

“…In this work, we have constructed and experimentally investigated frustrated arrays of dipoles forming two-dimensional artificial spin ices with different…”
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Skyrmion dynamics and skyrmion–bimeron crossover in antiferromagnetic thin nanodisks with a random distribution of magnetic impurities by Silva, R.L., Silva, R.C., Moura-Melo, W.A., Pereira, A.R.

“…Spin texture interacting with lattice defects is an important topic in condensed matter physics. This work investigates skyrmions in antiferromagnetic…”
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Skyrmion bound state and dynamics in an antiferromagnetic bilayer racetrack by Silva, R.C., Silva, R.L., Carvalho-Santos, V.L., Moura-Melo, W.A., Pereira, A.R.

“…We investigate the dynamics of two skyrmions lying in distinct layers of an antiferromagnetic bilayer system, consisting of nanostripes with the shape of…”
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Creation, transport and detection of imprinted magnetic solitons stabilized by spin-polarized current by Loreto, R.P., Moura-Melo, W.A., Pereira, A.R., Zhang, X., Zhou, Y., Ezawa, M., de Araujo, C.I.L.

“…With the recent proposition of skyrmion utilization in racetrack memories at room temperature, skyrmionics has become a very attractive field. However, for the…”
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Topological Insulator Particles As Optically Induced Oscillators: Toward Dynamical Force Measurements and Optical Rheology by Campos, W. H, Fonseca, J. M, de Carvalho, V. E, Mendes, J. B. S, Rocha, M. S, Moura-Melo, W. A

“…We report the first experimental study upon the optical trapping and manipulation of topological insulator (TI) particles. By virtue of the unique TI…”
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Magnetic vortex crystal formation in the antidot complement of square artificial spin ice by de Araujo, C. I. L., Silva, R. C., Ribeiro, I. R. B., Nascimento, F. S., Felix, J. F., Ferreira, S. O., Mól, L. A. S., Moura-Melo, W. A., Pereira, A. R.

“…We have studied ferromagnetic nickel thin films patterned with square lattices of elongated antidots that are negative analogues of square artificial spin ice…”
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Naked-eye visualization of geometric frustration effects in macroscopic spin ices by Gonçalves, R.S., Gomes, A.C.C., Loreto, R.P., Nascimento, F.S., Moura-Melo, W.A., Pereira, A.R., de Araujo, C.I.L.

“…•Naked eyed visualization of frustration in macroscopic system.•Very good agreement with Monte Carlo simulations.•Investigation of predicted degeneracy in…”
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Topological cutoff frequency in a slab waveguide: Penetration length in topological insulator walls by Melo, T.M., Viana, D.R., Moura-Melo, W.A., Fonseca, J.M., Pereira, A.R.

“…Electromagnetic waves propagating in a slab waveguide, whose walls consist of three-dimensional topological insulator, experience a topological cutoff…”
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Bound-states and polarized charged zero modes in three-dimensional topological insulators induced by a magnetic vortex by Fonseca, J.M., Moura-Melo, W.A., Pereira, A.R.

“…By coating a three-dimensional topological insulator (TI) with a ferromagnetic film supporting an in-plane magnetic vortex, one breaks the time-reversal…”
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Emission and absorption of photons and the black-body spectrum in Lorentz-odd electrodynamics by Fonseca, J.M., Gomes, A.H., Moura-Melo, W.A.

“…We study emission and absorption of radiation by non-relativistic electrons within the framework of a Lorentz-breaking electrodynamics in (3+1) dimensions. We…”
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Scattering of charge carriers in graphene induced by topological defects by Fonseca, J.M., Moura-Melo, W.A., Pereira, A.R.

“…We study the scattering of graphene quasiparticles by topological defects, represented by holes, pentagons and heptagons. For holes, we found that at low…”
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Emergence of skyrmion lattices and bimerons in chiral magnetic thin films with nonmagnetic impurities by Silva, R. L., Secchin, L. D., Moura-Melo, W. A., Pereira, A. R., Stamps, R. L.

“…Skyrmions are topologically protected field structures with particlelike characteristics that play important roles in several areas of science. Recently,…”
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