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arXiv · 2301.11896

Scale-free non-Hermitian skin effect in a boundary-dissipated spin chain

He-Ran Wang·Bo Li·Fei Song·Zhong Wang
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Abstract

We study the open XXZ spin chain with a PT-symmetric non-Hermitian boundary field. We find an interaction-induced scale-free non-Hermitian skin effect by using the coordinate Bethe ansatz. The steady state and the ground state in the PT broken phase are constructed, and the formulas of their eigen-energies in the thermodynamic limit are obtained. The differences between the many-body scale-free states and the boundary string states are explored, and the transition between the two at isotropic point is investigated. We also discuss an experimental scheme to verify our results.

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He-Ran Wang, Bo Li, Fei Song, Zhong Wang. 2023-01-27. Scale-free non-Hermitian skin effect in a boundary-dissipated spin chain. https://doi.org/10.21468/scipostphys.15.5.191

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