Physical Review A

Energy-dependent dynamical quantum phase transitions in quasicrystals

Shihao Ye, Ziheng Zhou, Niaz Ali Khan, Gao Xianlong

Published Apr 22, 2024• 12 citations

Abstract

Recently the role of the mobility edge in localization transitions has been extensively studied for one-dimensional tight-binding quasiperiodic models. In this work we study the mobility edge in a family of quasiperiodic systems evolving far from equilibrium, such as quench dynamics. We report numerical simulations of the Loschmidt echo based on a polynomial expansion-based technique with a moderate computational cost. Remarkably, we obtain an identical energy dependence on the equilibrium and dynamical quantum phase transitions of quasiperiodic models. The self-dual energy-independent localization model under quench dynamics exhibits energy-independent dynamical quantum phase transitions. On the other hand, self-dual energy-dependent localization models undergo energy-dependent dynamical quantum phase transitions. The results provide insights into energy-dependent dynamical localization transitions in quasiperiodic systems relevant to experiments.

DOI: 10.1103/physreva.109.043319

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