Magnetoelectric effect of a conducting sphere near a planar topological insulator
Por:
Martin-Ruiz, A., Rodriguez-Tzompantzi, Omar, Maze, J. R., Urrutia, L. F.
Publicada:
30 oct 2019
Categoría:
Atomic and molecular physics, and optics
Resumen:
When time-reversal symmetry is broken on its surface, topological
insulators exhibit a magnetoelectric response which is described by
axion electrodynamics. A direct consequence of this theory is the
appearance of a magnetic field that resembles the one produced by a
magnetic image monopole when a pointlike electric charge is located near
the surface of the material. In this paper, we investigate the more
realistic problem when the pointlike charge is replaced by a finite-size
sphere at constant potential. We calculate the electromagnetic fields
using the potential formulation in a particular bispherical coordinate
system. We find that the electromagnetic fields can be interpreted in
terms of point electric and image magnetic charges as if the medium were
the vacuum. As a manifestation of the magnetoelectric effect, we
highlight the resulting magnetic field, which we analyze in detail along
the symmetry axis, since such estimates could be useful in evaluating
the experimental possibility of its measurement via sensible
magnetometers. Our numerical estimates show that the proposed setup
provides a magnetic field strength in the range of 10-100 mG, which is
attainable with present day sensitivities in NV center diamond
magnetometers, for example.
Filiaciones:
Martin-Ruiz, A.:
Univ Nacl Autonoma Mexico, Intro Ciencias Nucl, Ciudad De Mexico 04510, Mexico
Univ Nacl Autonoma Mexico, Ctr Ciencias Complejidad, Ciudad De Mexico 04510, Mexico
Rodriguez-Tzompantzi, Omar:
Univ Nacl Autonoma Mexico, Intro Ciencias Nucl, Ciudad De Mexico 04510, Mexico
Maze, J. R.:
Pontificia Univ Catolica Chile, Fac Fis, Casilla 306, Santiago 22, Chile
Urrutia, L. F.:
Univ Nacl Autonoma Mexico, Intro Ciencias Nucl, Ciudad De Mexico 04510, Mexico
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