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arXiv · 1012.2084

Topological Insulator and the $θ$-vacuum in a system without boundaries

Kuang-Ting Chen·Patrick A. Lee
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Abstract

In this paper we address two questions concerning the effective action of a topological insulator in one and three dimensional space without boundaries, such as a torus. The first is whether a uniform $θ$-term with $θ=π$ is generated for a strong topological insulator. The second is whether such a term has observable consequences in the bulk. The answers to both questions are positive, but the observability in three dimension vanishes for infinite system size.

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Kuang-Ting Chen, Patrick A. Lee. 2010-12-10. Topological Insulator and the $θ$-vacuum in a system without boundaries. https://doi.org/10.1103/physrevb.83.125119

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