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arXiv · 0910.5954

Equivalent topological invariants of topological insulators

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

A time-reversal invariant topological insulator can be generally defined by the effective topological field theory with a quantized θcoefficient, which can only take values of 0 or π. This theory is generally valid for an arbitrarily interacting system and the quantization of the θinvariant can be directly measured experimentally. Reduced to the case of a non-interacting system, the θinvariant can be expressed as an integral over the entire three dimensional Brillouin zone. Alternatively, non-interacting insulators can be classified by topological invariants defined over discrete time-reversal invariant momenta. In this paper, we show the complete equivalence between the integral and the discrete invariants of the topological insulator.

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Zhong Wang, Xiao-Liang Qi, Shou-Cheng Zhang. 2012-09-23. Equivalent topological invariants of topological insulators. https://doi.org/10.1088/1367-2630%2F12%2F6%2F065007

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