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arXiv · 1211.5026

Criticality of the metal-topological insulator transition driven by disorder

Ai Yamakage·Kentaro Nomura·Ken-Ichiro Imura·Yoshio Kuramoto
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Abstract

Employing scaling analysis of the localization length, we deduce the critical exponent of the metal-topological insulator (TI) transitions induced by disorder. The obtained exponent nu~2.7 shows no conspicuous deviation from the value established for metal-ordinary insulator transitions in systems of the symplectic class. We investigate the topological phase diagram upon carrier doping to reveal the nature of the so-called topological Anderson insulator (TAI) region. The critical exponent of the metal-TAI transition is also first estimated, shown to be undistinguishable from the above value within the numerical error. By symmetry considerations we determine the explicit form of Rashba spin-orbit coupling in systems of C4v point group symmetry.

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Ai Yamakage, Kentaro Nomura, Ken-Ichiro Imura, Yoshio Kuramoto. 2013-04-17. Criticality of the metal-topological insulator transition driven by disorder. https://doi.org/10.1103/physrevb.87.205141

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