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arXiv · 2011.13720

Topological entanglement entropy of interacting disordered zigzag graphene ribbons

Young Heon Kim·Hye Jeong Lee·S. -R. Eric Yang
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Abstract

Interacting disordered zigzag graphene nanoribbons have fractional charges, are quasi-one-dimensional, and display an exponentially small gap. Our numerical computations showed that the topological entanglement entropy of these systems has a small finite but universal value, independent of the strength of the interaction and the disorder. The result that was obtained for the topological entanglement entropy shows that the disorder-free phase is critical and becomes unstable in the presence of disorder.

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Young Heon Kim, Hye Jeong Lee, S. -R. Eric Yang. 2020-11-27. Topological entanglement entropy of interacting disordered zigzag graphene ribbons. https://doi.org/10.1103/physrevb.103.115151

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