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arXiv · 1306.2125

Nonlinear Magneto-Optical and Magnetoelectric Phenomena in Topological Insulator Heterostructures

A. G. Mal'shukov·Hans Skarsvag·Arne Brataas
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Abstract

Three-dimensional topological insulator films in contact with magnetic layers exhibit intriguing magneto-optical and magnetoelectric phenomena, but little is known beyond the linear response regime. We demonstrate that the presence of two electric fields parallel to the surface of the film induces a perpendicular AC polarization, whereas a static polarization can be induced by applying a single circularly polarized electromagnetic wave. These phenomena are determined by the second-order susceptibility, which also controls the manner in which the anomalous Hall current is modulated by a perpendicular AC electric field. If the modulation frequency is low, the Hall effect is topologically protected and the nonlinear response vanishes.

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A. G. Mal'shukov, Hans Skarsvag, Arne Brataas. 2013-06-10. Nonlinear Magneto-Optical and Magnetoelectric Phenomena in Topological Insulator Heterostructures. https://doi.org/10.1103/physrevb.88.245122

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