Geometrically induced reversion of Hall current in a topological insulator cavity

Warlley H. Campos; Winder A. Moura-Melo; Jakson M. Fonseca

doi:10.1016/j.physleta.2016.11.037

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arXiv · 1608.06008

Geometrically induced reversion of Hall current in a topological insulator cavity

Warlley H. Campos·Winder A. Moura-Melo·Jakson M. Fonseca

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Abstract

An electric charge near the surface of a topological insulator induces an image magnetic monopole. Here, we show that if the topological insulator surface has a negative curvature, namely in the case of a semispherical cavity, the induced Hall current reverses its rotation as the electric charge crosses the semisphere geometric focus. Such a reversion is shown to be equivalent of inverting the charge of the image magnetic monopole. We also discuss upon the case of a semicylindrical cavity, where Hall current reversion appears to be feasible of probing in realistic experiments.

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Warlley H. Campos, Winder A. Moura-Melo, Jakson M. Fonseca. 2016-11-29. Geometrically induced reversion of Hall current in a topological insulator cavity. https://doi.org/10.1016/j.physleta.2016.11.037

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