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arXiv · 1110.3118

Localization and Mobility Gap in Topological Anderson Insulator

Yan-Yang Zhang·Rui-Lin Chu·Fu-Chun Zhang·Shun-Qing Shen
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Abstract

It has been proposed that disorder may lead to a new type of topological insulator, called topological Anderson insulator (TAI). Here we examine the physical origin of this phenomenon. We calculate the topological invariants and density of states of disordered model in a super-cell of 2-dimensional HgTe/CdTe quantum well. The topologically non-trivial phase is triggered by a band touching as the disorder strength increases. The TAI is protected by a mobility gap, in contrast to the band gap in conventional quantum spin Hall systems. The mobility gap in the TAI consists of a cluster of non-trivial subgaps separated by almost flat and localized bands.

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Yan-Yang Zhang, Rui-Lin Chu, Fu-Chun Zhang, Shun-Qing Shen. 2011-10-14. Localization and Mobility Gap in Topological Anderson Insulator. https://doi.org/10.1103/physrevb.85.035107

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