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
ISSN: 24699926
Editorial
AMER PHYSICAL SOC, ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA, Estados Unidos America
Tipo de documento: Article
Volumen: 100 Número: 4
Páginas:
WOS Id: 000493457800001

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