Topological Order Parameters for Interacting Topological Insulators

Zhong Wang; Xiao-Liang Qi; Shou-Cheng Zhang

doi:10.1103/physrevlett.105.256803

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arXiv · 1004.4229

Topological Order Parameters for Interacting Topological Insulators

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

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Abstract

We propose a topological order parameter for interacting topological insulators, expressed in terms of the full Green's functions of the interacting system. We show that it is exactly quantized for a time reversal invariant topological insulator, and it can be experimentally measured through the topological magneto-electric effect. This topological order parameter can be applied to both interacting and disordered systems, and used for determining their phase diagrams.

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Zhong Wang, Xiao-Liang Qi, Shou-Cheng Zhang. 2010-12-13. Topological Order Parameters for Interacting Topological Insulators. https://doi.org/10.1103/physrevlett.105.256803

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