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arXiv · 2203.03995

Driving-induced multiple ${\cal PT}$-symmetry breaking transitions and reentrant localization transitions in non-Hermitian Floquet quasicrystals

Longwen Zhou·Wenqian Han
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Abstract

The cooperation between time-periodic driving fields and non-Hermitian effects could endow systems with distinctive spectral and transport properties. In this work, we uncover an intriguing class of non-Hermitian Floquet matter in one-dimensional quasicrystals, which is characterized by the emergence of multiple driving-induced ${\cal PT}$-symmetry breaking/restoration, mobility edges, and reentrant localization transitions. These findings are demonstrated by investigating the spectra, level statistics, inverse participation ratios and wavepacket dynamics of a periodically quenched nonreciprocal Harper model. Our results not only unveil the richness of localization phenomena in driven non-Hermitian quasicrystals, but also highlight the advantage of Floquet approach in generating unique types of nonequilibrium phases in open systems.

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Longwen Zhou, Wenqian Han. 2022-03-08. Driving-induced multiple ${\cal PT}$-symmetry breaking transitions and reentrant localization transitions in non-Hermitian Floquet quasicrystals. https://doi.org/10.1103/physrevb.106.054307

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