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arXiv · 2305.12342

Disorder-Induced Entanglement Phase Transitions in Non-Hermitian Systems with Skin Effects

Kai Li·Ze-Chuan Liu·Yong Xu
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Abstract

Non-Hermitian dynamics is ubiquitous in various physical systems. While recent study shows that such a dynamics leads to an area-law scaling of the entanglement entropy due to the non-Hermitian skin effects, it remains unclear how disorder changes the behavior of the entanglement entropy in a non-Hermitian system with skin effects. Here we study the dynamics of a many-body state of free fermions in the paradigmatic Hatano-Nelson model with open boundaries, and find that the area-law behavior of the entanglement entropy in the pristine Hatano-Nelson model develops into a logarithmic scaling for small disorder strength. As we further increase the disorder strength, the system reenters an area-law regime through an entanglement phase transition. At the critical point, the entanglement entropy exhibits a universal algebraic scaling. We further demonstrate the absence of a conformal invariance in the log-law regime by examining the subsystem entanglement entropy, the connected correlation function and the mutual information. Finally, we show the existence of disorder induced entanglement phase transitions in the Hatano-Nelson model with periodic boundaries.

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Kai Li, Ze-Chuan Liu, Yong Xu. 2026-08-04. Disorder-Induced Entanglement Phase Transitions in Non-Hermitian Systems with Skin Effects. https://doi.org/10.22331/q-2026-08-07-2186

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