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arXiv · 2108.00972

Disorder-driven phase transitions in bosonic fractional quantum Hall liquids

Chao Han·Zhao Liu
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Abstract

We investigate the disorder-driven phase transitions in bosonic fractional quantum Hall liquids at filling factors $f=1/2$ and $f=1$ in the lowest Landau level. We use the evolution of ground-state entanglement entropy, fidelity susceptibility, and Hall conductance with increasing disorder strength to identify the underlying phase transitions. The critical disorder strengths obtained from these different quantities are consistent with each other, validating the reliability of our numerical calculations based on exact diagonalization. At $f=1/2$, we observe a clear transition from the bosonic Laughlin state to a trivial insulating phase. At $f=1$, we identify a direct phase transition from the non-Abelian bosonic Moore-Read state to a trivial insulating phase, although some signs of a disorder-induced intermediate fractional quantum Hall phase were recently reported for the $f=5/2$ fermionic cousin.

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Chao Han, Zhao Liu. 2021-08-02. Disorder-driven phase transitions in bosonic fractional quantum Hall liquids. https://doi.org/10.1103/physrevb.105.045104

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