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arXiv · 2108.08630

Transition from metal to higher-order topological insulator driven by random flux

Chang-An Li·Song-Bo Zhang·Jan Carl Budich·Björn Trauzettel
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Abstract

Random flux is commonly believed to be incapable of driving full metal-insulator transitions in non-interacting systems. Here we show that random flux can after all induce a full metal-band insulator transition in the two-dimensional Su-Schrieffer-Heeger model. Remarkably, we find that the resulting insulator can be an extrinsic higher-order topological insulator with zero-energy corner modes in proper regimes, rather than a conventional Anderson insulator. Employing both level statistics and finite-size scaling analysis, we characterize the metal-band insulator transition and numerically extract its critical exponent as $ν=2.48\pm0.08$. To reveal the physical mechanism underlying the transition, we present an effective band structure picture based on the random flux averaged Green's function.

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Chang-An Li, Song-Bo Zhang, Jan Carl Budich, Björn Trauzettel. 2022-08-29. Transition from metal to higher-order topological insulator driven by random flux. https://doi.org/10.1103/physrevb.106.l081410

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