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arXiv · 1911.09819

Toy model of boundary states with spurious topological entanglement entropy

Kohtaro Kato·Fernando G. S. L. Brandão
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Abstract

Topological entanglement entropy has been extensively used as an indicator of topologically ordered phases. We study the conditions needed for two-dimensional topologically trivial states to exhibit spurious contributions that contaminates topological entanglement entropy. We show that if the state at the boundary of a subregion is a stabilizer state, then it has a non-zero spurious contribution to the region if and only if, the state is in a non-trivial one-dimensional $G_1\times G_2$ symmetry-protected-topological (SPT) phase. However, we provide a candidate of a boundary state that has a non-zero spurious contribution but does not belong to any such SPT phase.

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Kohtaro Kato, Fernando G. S. L. Brandão. 2019-11-22. Toy model of boundary states with spurious topological entanglement entropy. https://doi.org/10.1103/physrevresearch.2.032005

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