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arXiv · 1212.6191

Statistical Topological Insulators

I. C. Fulga·B. van Heck·J. M. Edge·A. R. Akhmerov
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Abstract

We define a class of insulators with gapless surface states protected from localization due to the statistical properties of a disordered ensemble, namely due to the ensemble's invariance under a certain symmetry. We show that these insulators are topological, and are protected by a $\mathbb{Z}_2$ invariant. Finally, we prove that every topological insulator gives rise to an infinite number of classes of statistical topological insulators in higher dimensions. Our conclusions are confirmed by numerical simulations.

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I. C. Fulga, B. van Heck, J. M. Edge, A. R. Akhmerov. 2012-12-26. Statistical Topological Insulators. https://doi.org/10.1103/physrevb.89.155424

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