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arXiv · 2101.04115

Yang-Lee edge singularity triggered entanglement transition

Shao-Kai Jian·Zhi-Cheng Yang·Zhen Bi·Xiao Chen
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Abstract

We show that a class of $\mathcal{PT}$ symmetric non-Hermitian Hamiltonians realizing the Yang-Lee edge singularity exhibits an entanglement transition in the long-time steady state evolved under the Hamiltonian. Such a transition is induced by a level crossing triggered by the critical point associated with the Yang-Lee singularity and hence is first-order in nature. At the transition, the entanglement entropy of the steady state jumps discontinuously from a volume-law to an area-law scaling. We exemplify this mechanism using a one-dimensional transverse field Ising model with additional imaginary fields, as well as the spin-1 Blume-Capel model and the three-state Potts model. We further make a connection to the forced-measurement induced entanglement transition in a Floquet non-unitary circuit subject to continuous measurements followed by post-selections. Our results demonstrate a new mechanism for entanglement transitions in non-Hermitian systems harboring a critical point.

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Shao-Kai Jian, Zhi-Cheng Yang, Zhen Bi, Xiao Chen. 2021-01-11. Yang-Lee edge singularity triggered entanglement transition. https://doi.org/10.1103/physrevb.104.l161107

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