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arXiv · 1008.0531

Dynamics of the (spin-) Hall effect in topological insulators and graphene

Balázs Dóra·Roderich Moessner
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Abstract

A single two-dimensional Dirac cone with a mass gap produces a quantized (spin-) Hall step in the absence of magnetic field. What happens in strong electric fields? This question is investigated by analyzing time evolution and dynamics of the (spin-) Hall effect. After switching on a longitudinal electric field, a stationary Hall current is reached through damped oscillations. The Hall conductivity remains quantized as long as the electric field (E) is too weak to induce Landau-Zener transitions, but quantization breaks down for strong fields and the conductivity decreases as 1/sqrt{E}. These apply to the (spin-) Hall conductivity of graphene and the Hall and magnetoelectric response of topological insulators.

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Balázs Dóra, Roderich Moessner. 2010-08-03. Dynamics of the (spin-) Hall effect in topological insulators and graphene. https://doi.org/10.1103/physrevb.83.073403

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