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arXiv:2105.09793 · Journal of Physics Condensed Matter

Entanglement entropy of non-Hermitian free fermions

Yibin Guo, Yi-Cong Yu, Rui-Zhen Huang, Li‐Ping Yang, Run-Ze Chi, Haijun Liao, Tao Xiang

Published Aug 26, 2021• 36 citations
arXivHTMLPDF

Abstract

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.

DOI
10.1088/1361-648x/ac216e

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