The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

Dimitris G Angelakis - One of the best experts on this subject based on the ideXlab platform.

  • dirac equation on a square waveguide lattice with site dependent coupling strengths and the gravitational aharonov bohm Effect
    arXiv: Quantum Physics, 2020
    Co-Authors: Christian Koke, Changsuk Noh, Dimitris G Angelakis
    Abstract:

    The main objective of this work is to present a theoretical proposal for an implementation of the $(2 + 1)$-dimensional Dirac equation in classical gravitational and electromagnetic backgrounds in a two-dimensional waveguide array. For this, a framework for achieving site-dependent Effective coupling constants in two-dimensional waveguide arrays is developed. Implementability of the Dirac equation under the proposed scheme puts minor demands on gauge and spacetime backgrounds; however, a wide array of physical spacetimes, such as all vacuum and static solutions, prove to be implementable. As an interesting and instructive example, we discuss a tabletop realization of the gravitational Aharonov-Bohm Effect: After devising a thought experiment in which signatures of the gravitational Aharonov-Bohm Effect could be detected, we briefly discuss how the analogue of such a setting can in principle be implemented using the proposed waveguide setup.

  • dirac equation on a square waveguide lattice with site dependent coupling strengths and the gravitational aharonov bohm Effect
    Physical Review A, 2020
    Co-Authors: Christian Koke, Changsuk Noh, Dimitris G Angelakis
    Abstract:

    The main objective of this work is to present a theoretical proposal for an implementation of the ($2+1$)-dimensional Dirac equation in classical gravitational and electromagnetic backgrounds, in a two-dimensional waveguide array. For this, a framework for achieving site-dependent Effective coupling constants in two-dimensional waveguide arrays is developed. Implementability of the Dirac equation under the proposed scheme puts minor demands on gauge and spacetime backgrounds; however, a wide array of physical spacetimes, such as all vacuum and static solutions, prove to be implementable. As an interesting and instructive example, we discuss a tabletop realization of the gravitational Aharonov-Bohm Effect: After devising a thought experiment in which signatures of the gravitational Aharonov-Bohm Effect could be detected, we briefly discuss how the analog of such a setting can in principle be implemented using the proposed waveguide setup.

Alexandre Buzdin - One of the best experts on this subject based on the ideXlab platform.

  • Electromagnetic proximity Effect in planar superconductor-ferromagnet structures
    Applied Physics Letters, 2018
    Co-Authors: Sergey Mironov, A Mel'nikov, Alexandre Buzdin
    Abstract:

    The spread of the Cooper pairs into the ferromagnet in proximity coupled superconductor-ferromagnet (SF) structures is shown to cause a strong inverse electromagnetic phenomenon, namely, the long-range transfer of the magnetic field from the ferromagnet to the superconductor. Contrary to the previously investigated inverse proximity Effect resulting from the spin polarization of superconducting surface layer, the characteristic length of the above inverse electrodynamic Effect is of the order of the London penetration depth, which usually much larger than the superconducting coherence length. The corresponding spontaneous currents appear even in the absence of the stray field of the ferromagnet and are generated by the vector-potential of magnetization near the S/F interface and they should be taken into account at the design of the nanoscale S/F devices. Similarly to the well-known Aharonov-Bohm Effect, the discussed phenomenon can be viewed as a manifestation of the role of vector potential in quantum physics.

  • electromagnetic proximity Effect in planar superconductor ferromagnet structures
    Applied Physics Letters, 2018
    Co-Authors: Sergey Mironov, Alexandre Buzdin, A S Melnikov
    Abstract:

    The spread of Cooper pairs in a ferromagnet in proximity coupled superconductor-ferromagnet structures is shown to cause a strong inverse electromagnetic phenomenon, namely, the long-range transfer of the magnetic field from the ferromagnet to the superconductor. Contrary to the previously investigated inverse proximity Effect resulting from the spin polarization of a superconducting surface layer, the characteristic length of the above inverse electrodynamic Effect is of the order of the London penetration depth, which usually is much larger than the superconducting coherence length. The corresponding spontaneous currents appear even in the absence of the stray field of the ferromagnet and are generated by the vector-potential of magnetization near the S/F interface, and they should be taken into account in the design of nanoscale S/F devices. Similarly to the well-known Aharonov-Bohm Effect, the discussed phenomenon can be viewed as a manifestation of the role of vector potential in quantum physics.

Faizuddin Ahmed - One of the best experts on this subject based on the ideXlab platform.

Joseph Maciejko - One of the best experts on this subject based on the ideXlab platform.

  • spin aharonov bohm Effect and topological spin transistor
    Bulletin of the American Physical Society, 2010
    Co-Authors: Joseph Maciejko, Eunah Kim
    Abstract:

    Ever since its discovery, the electron spin has only been measured or manipulated through the application of an electromagnetic force acting on the associated magnetic moment. In this work, we propose a spin Aharonov-Bohm Effect in which the electron spin is controlled by a magnetic flux while no electromagnetic field is acting on the electron. Such a nonlocal spin manipulation is realized in an Aharonov-Bohm ring made from the recently discovered quantum spin Hall insulator, by taking advantage of the defining property of the quantum spin Hall edge states: the one-to-one correspondence between spin polarization and direction of propagation. The proposed setup can be used to realize a new spintronics device, the topological spin transistor, in which the spin rotation is completely controlled by a magnetic flux of $hc/2e$, independently of the details of the sample.

K Bakke - One of the best experts on this subject based on the ideXlab platform.

  • on the interaction of the scalar field with a coulomb type potential in a spacetime with a screw dislocation and the aharonov bohm Effect for bound states
    European Physical Journal Plus, 2018
    Co-Authors: R. L. L. Vitória, K Bakke
    Abstract:

    We investigate topological Effects on the interaction of a scalar field with a Coulomb-type potential in a spacetime with a screw dislocation (space-like dislocation). We also consider the topological defect with an internal magnetic field. Later, we investigate the interaction of a scalar field with a Coulomb-type potential plus another Coulomb-type potential (gauge potential), a uniform magnetic field, the Klein-Gordon oscillator and a linear scalar potential in this topological defect spacetime. Then, by searching for analytical solutions to the Klein-Gordon equation in the spacetime with a screw dislocation, we obtain analogues Effects of the Aharonov-Bohm Effect for bound states.

  • aharonov bohm Effect for bound states in relativistic scalar particle systems in a spacetime with a spacelike dislocation
    International Journal of Modern Physics D, 2018
    Co-Authors: R. L. L. Vitória, K Bakke
    Abstract:

    We investigate the analog Effect of the Aharonov–Bohm Effect for bound states in two relativistic quantum systems in a spacetime with a spacelike dislocation. We assume that the topological defect has an internal magnetic flux. Then, we analyze the interaction of a charged particle with a uniform magnetic field in this topological defect spacetime, and thus, we extend this analysis to the confinement of a hard-wall potential and a linear scalar potential. Later, the interaction of the Klein–Gordon oscillator with a uniform magnetic field is analyzed. We first focus on the Effects of torsion that stem from the spacetime with a spacelike dislocation and the geometric quantum phase. Then, we analyze the Effects of torsion and the geometric quantum phase under the presence of a hard-wall potential and a linear scalar potential.

  • aharonov bohm Effect for bound states in relativistic scalar particle systems in a spacetime with a space like dislocation
    arXiv: Quantum Physics, 2017
    Co-Authors: R. L. L. Vitória, K Bakke
    Abstract:

    We investigate the analogue Effect of the Aharonov-Bohm Effect for bound states in two relativistic quantum systems in a spacetime with a space-like dislocation. We assume that the topological defect has an internal magnetic flux. Then, we analyse the interaction of a charged particle with a uniform magnetic field in this topological defect spacetime, and thus, we extend this analysis to the confinement to a hard-wall potential and a linear scalar potential. Later, the interaction of the Klein-Gordon oscillator with a uniform magnetic field is analysed. We first focus on the Effects of torsion that stem from the spacetime with a space-like dislocation and the geometric quantum phase. Then, we analyse the Effects of torsion and the geometric quantum phase under the presence of a hard-wall potential and a linear scalar potential.

  • torsion Effects on a relativistic position dependent mass system
    arXiv: Quantum Physics, 2016
    Co-Authors: R. L. L. Vitória, K Bakke
    Abstract:

    We analyse a relativistic scalar particle with a position-dependent mass in a spacetime with a space-like dislocation by showing that relativistic bound states solutions can be achieved. Further, we consider the presence of the Coulomb potential and analyse the relativistic position-dependent mass system subject to the Coulomb potential in the spacetime with a space-like dislocation. We also show that a new set of relativistic bound states solutions can be obtained, where there also exists the influence of torsion of the relativistic energy levels. Finally, we investigate an analogue of the Aharonov-Bohm Effect for bound states in this position-dependent mass in a spacetime with a space-like dislocation.

  • aharonov anandan quantum phases and landau quantization associated with a magnetic quadrupole moment
    Annals of Physics, 2015
    Co-Authors: I C Fonseca, K Bakke
    Abstract:

    Abstract The arising of geometric quantum phases in the wave function of a moving particle possessing a magnetic quadrupole moment is investigated. It is shown that an Aharonov–Anandan quantum phase (Aharonov and Anandan, 1987) can be obtained in the quantum dynamics of a moving particle with a magnetic quadrupole moment. In particular, it is obtained as an analogue of the scalar Aharonov–Bohm Effect for a neutral particle (Anandan, 1989). Besides, by confining the quantum particle to a hard-wall confining potential, the dependence of the energy levels on the geometric quantum phase is discussed and, as a consequence, persistent currents can arise from this dependence. Finally, an analogue of the Landau quantization is discussed.