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arXiv · 1201.6431

Topological invariants for interacting topological insulators with inversion symmetry

Zhong Wang·Xiao-Liang Qi·Shou-Cheng Zhang
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Abstract

For interacting Z_2 topological insulators with inversion symmetry, we propose a simple topological invariant expressed in terms of the parity eigenvalues of the interacting Green's function at time-reversal invariant momenta. We derive this result from our previous formula involving the integral over the frequency-momenta space. This formula greatly simplifies the explicit calculation of Z_2 topological invariants in inversion symmetric insulators with strong interactions.

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Zhong Wang, Xiao-Liang Qi, Shou-Cheng Zhang. 2012-04-18. Topological invariants for interacting topological insulators with inversion symmetry. https://doi.org/10.1103/physrevb.85.165126

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