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arXiv · 1303.3425

Z2 topological invariants in two dimensions from quantum Monte Carlo

Thomas C. Lang·Andrew M. Essin·Victor Gurarie·Stefan Wessel
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Abstract

We employ quantum Monte Carlo techniques to calculate the $Z_2$ topological invariant in a two-dimensional model of interacting electrons that exhibits a quantum spin Hall topological insulator phase. In particular, we consider the parity invariant for inversion-symmetric systems, which can be obtained from the bulk's imaginary-time Green's function after an appropriate continuation to zero frequency. This topological invariant is used here in order to study the trivial-band to topological-insulator transitions in an interacting system with spin-orbit coupling and an explicit bond dimerization. We discuss the accessibility and behavior of this topological invariant within quantum Monte Carlo simulations.

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Thomas C. Lang, Andrew M. Essin, Victor Gurarie, Stefan Wessel. 2013-03-14. Z2 topological invariants in two dimensions from quantum Monte Carlo. https://doi.org/10.1103/physrevb.87.205101

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