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arXiv · 1012.3804

Surface quantized anomalous Hall current and magneto-electric effect in magnetically disordered topological insulators

Kentaro Nomura·Naoto Nagaosa
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Abstract

We study theoretically the role of quenched magnetic disorder at the surface of a topological insulator by numerical simulation and scaling analysis. It is found that all the surface states are localized while the transverse conductivity is quantized to be $\pm {{e^2} \over {2 h}}$ as long as the Fermi energy is within the bulk gap. This greatly facilitates the realization of the topological magnetoelectric effect proposed by Qi {\it et al.} (Phys. Rev. B\textbf{78}, 195424 (2008)) with the surface magnetization direction being controlled by the simultaneous application of magnetic and electric fields .

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Kentaro Nomura, Naoto Nagaosa. 2011-01-28. Surface quantized anomalous Hall current and magneto-electric effect in magnetically disordered topological insulators. https://doi.org/10.1103/physrevlett.106.166802

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