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

  title={Quantum phase transition in a non-Hermitian XY spin chain with global complex transverse field},
  author={Yu-Guo Liu and Lu Xu and Zhi Li},
  journal={Journal of Physics: Condensed Matter},
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… Expand


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