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arXiv · 2105.09793

Entanglement Entropy of Non-Hermitian Free Fermions

Yi-Bin Guo·Yi-Cong Yu·Rui-Zhen Huang·Li-Ping Yang·Run-Ze Chi·Hai-Jun Liao·Tao Xiang
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Abstract

We study the entanglement properties of non-Hermitian free fermionic models with translation symmetry using the correlation matrix technique. Our results show that the entanglement entropy has a logarithmic correction to the area law in both one-dimensional and two-dimensional systems. For any one-dimensional one-band system, we prove that each Fermi point of the system contributes exactly 1/2 to the coefficient c of the logarithmic correction. Moreover, this relation between c and Fermi point is verified for more general one-dimensional and two-dimensional cases by numerical calculations and finite-size scaling analysis. In addition, we also study the single-particle and density-density correlation functions.

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Yi-Bin Guo, Yi-Cong Yu, Rui-Zhen Huang, Li-Ping Yang, Run-Ze Chi, Hai-Jun Liao, Tao Xiang. 2021-05-20. Entanglement Entropy of Non-Hermitian Free Fermions. https://doi.org/10.1088/1361-648x%2Fac216e

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