arXiv subjects

L. R. Ribeiro

Publications and source records attributed to L. R. Ribeiro.

9 recordsLinked to original sources

arXiv2017

Analogue of the quantum Hall effect for neutral particles with magnetic dipole moment

In this paper we investigate a possibility for the existence of an analog of the Quantum Hall Effect for neutral particles with a permanent magnetic moment $μ$ in the presence of crossed inhomogeneous magnetic and electric fields. We predict the appearance of Hall conductivity $σ_H=(e^2/h)ν(μ)$ with the Landau filling factor $ν(μ)\propto μ^2$. The estimates of the model parameters suggest quite an optimistic possibility to experimentally verify this prediction in optically trapped clouds of atomic BEC.

cond-mat.str-el↗

arXiv2012

An Analogy of the Quantum Hall Condutivity in a Lorentz-symmetry Violation Setup

We investigated some influences of unconventional physics, such Lorentz-symmetry violation, for quantum mechanical systems. In this context, we calculated a important contribution for Standard Model Extension. In the non-relativistic limit, we obtained a analogy of the Landau levels and the quantum Hall conductivity related to this contribution for low energy systems.

hep-th↗

arXiv2008

Landau quantization for a neutral particle in presence of topological defects

In this paper we study the Landau levels in the non-relativistic dynamics of a neutral particle which possesses a permanent magnetic dipole moment interacting with an external electric field in the curved spacetime background with the presence or absence of a torsion field. The eigenfunction and eigenvalues of Hamiltonian are obtained. We show that the presence of the topological defect breaks the infinite degeneracy of the Landau levels arising in this system. We also apply a duality transformation to discuss this same quantization for a dynamics of a neutral particle with a permanent electric dipole moment.

hep-th↗

arXiv2008

Lorentz symmetry violation and an Analog of Landau levels

Within the context of Lorentz violating extended electrodynamics, we study an analog of Landau quantization for a system where a neutral particle moves in the presence of an electromagnetic field and a constant four-vector that breaks Lorentz symmetry. The nonrelativistic Hamiltonian associated to this system is obtained using the Foldy-Wouthuysen transformation for a Dirac spinor. The degenerated energy spectrum is obtained for a time-like and a space-like parameter Lorentz-breaking vector. The energy dependence of the cyclotron rotation direction in terms of supersymmetric quantum mechanics is analyzed.

hep-th↗

arXiv2007

Landau Analog Levels for Dipoles in the Noncommutative Space and Phase Space

In the present contribution we investigate the Landau analog energy quantization for neutral particles, that possesses a nonzero permanent magnetic and electric dipole moments, in the presence of an homogeneous electric and magnetic external fields in the context of the noncommutative quantum mechanics. Also, we analyze the Landau--Aharonov--Casher and Landau--He--McKellar--Wilkens quantization due to noncommutative quantum dynamics of magnetic and electric dipoles in the presence of an external electric and magnetic fields and the energy spectrum and the eigenfunctions are obtained. Furthermore, we have analyzed Landau quantization analogs in the noncommutative phase space, and we obtain also the energy spectrum and the eigenfunctions in this context.

hep-th↗

arXiv2007

The geometric phases in a background with Lorentz-symmetry violation

We analyze the nonrelativistic quantum dynamics of a single neutral spin half particle, with non-zero magnetic and electric dipole moments, moving in an external electromagnetic field in presence of Lorentz symmetry violation background. Also, we study the geometric phase for this model taking into account the parameter that breaks the Lorentz symmetry. We investigate the He-McKellar-Wilkens effect in this context and we verify that Lorentz violation parameter contribute to increase the electric dipole moment of the particle.

hep-th↗

arXiv2007

The Noncommutative Anandan's Quantum Phase

In this work we study the noncommutative nonrelativistic quantum dynamics of a neutral particle, that possesses permanent magnetic and electric dipole momenta, in the presence of an electric and magnetic fields. We use the Foldy-Wouthuysen transformation of the Dirac spinor with a non-minimal coupling to obtain the nonrelativistic limit. In this limit, we will study the noncommutative quantum dynamics and obtain the noncommutative Anandan's geometric phase. We analyze the situation where magnetic dipole moment of the particle is zero and we obtain the noncommutative version of the He-McKellar-Wilkens effect. We demonstrate that this phase in the noncommutative case is a geometric dispersive phase. We also investigate this geometric phase considering the noncommutativity in the phase space and the Anandan's phase is obtained.

hep-th↗

arXiv2005

Landau Levels Analog to Electric Dipole

In this letter we study the quantum dyamics of a neutral particle in the presence of an external magnetic field. We demonstrate in a specific field-dipole configuration that we have a quantization similar to the Landau Levels. We investigate this quantization motivated by the recent analysis of Landau-Aharonov-Casher(LAC) quantization of Ericsson and Sjöqvist[Phys Rev. A {\bf 65} 013607 (2001)]. The energy eigenfuction and eigenvalues are obtained.

quant-ph↗

arXiv2005

Landau Quantization of Neutral Particles in an External Field

The quantum dynamics of an induced electric dipole in the presence of a configuration of crossed electric and magnetic fields is analyzed. This field configuration confines the dipole in a plane and produces a coupling similar to the coupling of a charged particle in the presence of external magnetic field. In this work we investigate the analog of Landau levels in induced electric dipoles in a sistem of neutral particles. The energy levels and eigenfunctions are obtained exactly.

hep-th↗