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arXiv · 2405.19155

Fate of non-Hermitian free fermions with Wannier-Stark ladder

Han-Ze Li·Minhui Wan·Jian-Xin Zhong
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Abstract

The Wannier-Stark localization dynamically alters the entanglement behavior of non-Hermitian free fermions. Utilizing the single-particle correlation matrix technique, we analyze the effective Hamiltonian of these fermions with a Wannier-Stark ladder. Under open boundary conditions, we observe the steady state half-chain entanglement entropy and identify two distinct area law regions and an algebraic scaling region. Finite-size scaling analysis reveals critical scaling behavior of the half-chain entanglement entropy. Notably, the system demonstrates unique entanglement characteristics under periodic boundary conditions, which diverge from the (1+1)d conformal field theory predictions for Anderson localization. Our findings highlight novel entanglement phases emerging from the interplay between the non-Hermitian skin effect and disorder-free localization.

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Han-Ze Li, Minhui Wan, Jian-Xin Zhong. 2024-05-29. Fate of non-Hermitian free fermions with Wannier-Stark ladder. https://doi.org/10.1103/physrevb.110.094310

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