Localized surfaces of three dimensional topological insulators

Yang-Zhi Chou; Rahul M. Nandkishore; Leo Radzihovsky

doi:10.1103/physrevb.99.165108

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arXiv · 1901.05464

Localized surfaces of three dimensional topological insulators

Yang-Zhi Chou·Rahul M. Nandkishore·Leo Radzihovsky

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Abstract

We study the surface of a three-dimensional spin chiral $\mathrm{Z}_2$ topological insulator (class CII), demonstrating the possibility of its localization. This arises through an interplay of interaction and statistically-symmetric disorder, that confines the gapless fermionic degrees of freedom to a network of one-dimensional helical domain-walls that can be localized. We identify two distinct regimes of this gapless insulating phase, a `clogged' regime wherein the network localization is induced by its junctions between otherwise metallic helical domain-walls, and a `fully localized' regime of localized domain-walls. The experimental signatures of these regimes are also discussed.

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Yang-Zhi Chou, Rahul M. Nandkishore, Leo Radzihovsky. 2019-04-08. Localized surfaces of three dimensional topological insulators. https://doi.org/10.1103/physrevb.99.165108

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