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arXiv · 1608.06634

Disorder effects in correlated topological insulators

Hsiang-Hsuan Hung·Aaron Barr·Emil Prodan·Gregory A. Fiete
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Abstract

Using exact diagonalization and quantum Monte Carlo calculations we investigate the effects of disorder on the phase diagram of both non-interacting and interacting models of two-dimensional topological insulators. In the fermion sign problem-free interacting models we study, electron-electron interactions are described by an on-site repulsive Hubbard interaction and disorder is included via the one-body hopping operators. In both the non-interacting and interacting models we make use of recent advances in highly accurate real-space numerical evaluation of topological invariants to compute phase boundaries, and in the non-interacting models determine critical exponents of the transitions. We find different models exhibit distinct stability conditions of the topological phase with respect to interactions and disorder. We provide a general analytical theory that accurately predicts these trends.

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Hsiang-Hsuan Hung, Aaron Barr, Emil Prodan, Gregory A. Fiete. 2016-08-23. Disorder effects in correlated topological insulators. https://doi.org/10.1103/physrevb.94.235132

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