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arXiv · 2012.07374

Quantum phase transition in a non-Hermitian XY spin chain with global complex transverse field

Yu-Guo Liu·Lu Xu·Zhi Li
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Abstract

In this work, we investigate the quantum phase transition in a non-Hermitian XY spin chain. The phase diagram shows that the critical points of Ising phase transition expand into a critical transition zone after introducing a non-Hermitian effect. By analyzing the non-Hermitian gap and long-range correlation function, one can distinguish different phases by means of different gap features and decay properties of correlation function, a tricky problem in traditional XY model. Furthermore, the results reveal the relationship among different regions of the phase diagram, non-Hermitian energy gap and long-range correlation function.

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Yu-Guo Liu, Lu Xu, Zhi Li. 2020-12-14. Quantum phase transition in a non-Hermitian XY spin chain with global complex transverse field. https://doi.org/10.1088/1361-648x/ac00dd

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