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arXiv · 1512.03233

The topological Anderson insulator phase in the Kane-Mele model

Abstract

It has been proposed that adding disorder to a topologically trivial mercury telluride/cadmium telluride (HgTe/CdTe) quantum well can induce a transition to a topologically nontrivial state. The resulting state was termed topological Anderson insulator and was found in computer simulations of the Bernevig-Hughes-Zhang model. Here, we show that the topological Anderson insulator is a more universal phenomenon and also appears in the Kane-Mele model of topological insulators on a honeycomb lattice. We numerically investigate the interplay of the relevant parameters, and establish the parameter range in which the topological Anderson insulator exists. A staggered sublattice potential turns out to be a necessary condition for the transition to the topological Anderson insulator. For weak enough disorder, a calculation based on the lowest-order Born approximation reproduces quantitatively the numerical data. Our results thus considerably increase the number of candidate materials for the topological Anderson insulator phase.

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BibTeXRIS

Christoph P. Orth, Tibor Sekera, Christoph Bruder, Thomas L. Schmidt. 2015-12-10. The topological Anderson insulator phase in the Kane-Mele model. https://doi.org/10.1038/srep24007

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