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arXiv · 2405.13282

Quantum criticality of generalized Aubry-Andr\'{e} models with exact mobility edges using fidelity susceptibility

Yu-Bin Liu·Wen-Yi Zhang·Tian-Cheng Yi·Liangsheng Li·Maoxin Liu·Wen-Long You
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Abstract

In this study, we explore the quantum critical phenomena in generalized Aubry-Andr\'{e} models, with a particular focus on the scaling behavior at various filling states. Our approach involves using quantum fidelity susceptibility to precisely identify the mobility edges in these systems. Through a finite-size scaling analysis of the fidelity susceptibility, we are able to determine both the correlation-length critical exponent and the dynamical critical exponent at the critical point of the generalized Aubry-Andr\'{e} model. Based on the Diophantine equation conjecture, we can determines the number of subsequences of the Fibonacci sequence and the corresponding scaling functions for a specific filling fraction, as well as the universality class. Our findings demonstrate the effectiveness of employing the generalized fidelity susceptibility for the analysis of unconventional quantum criticality and the associated universal information of quasiperiodic systems in cutting-edge quantum simulation experiments.

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Yu-Bin Liu, Wen-Yi Zhang, Tian-Cheng Yi, Liangsheng Li, Maoxin Liu, Wen-Long You. 2024-05-22. Quantum criticality of generalized Aubry-Andr\'{e} models with exact mobility edges using fidelity susceptibility. https://doi.org/10.1103/physreve.109.054123

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