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arXiv · 2308.11968

Tunable Aharonov-Bohm cages through anti-$\mathcal{PT}$-symmetric imaginary couplings

S. M. Zhang·H. S. Xu·L. Jin
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Abstract

The Aharonov-Bohm (AB) cage enables localized confinement with nondiffractive propagation for arbitrary excitation. In this study, we introduce an anti-parity-time (anti-$\mathcal{PT}$) symmetric imaginary coupling in a generalized Creutz ladder to construct a non-Hermitian AB cage with tunable flat-band energy. We investigate compact localized states and complete localization dynamics, and show that non-Hermiticity affects the localization probability distributions and increases the oscillation period of the AB cage dynamics. Non-Hermitian engineering of the decoupled core of the AB cage is the essential point in our proposal. Our approach is widely applicable to a more general situation and can facilitate the manipulation of localization in physics.

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S. M. Zhang, H. S. Xu, L. Jin. 2023-08-23. Tunable Aharonov-Bohm cages through anti-$\mathcal{PT}$-symmetric imaginary couplings. https://doi.org/10.1103/physreva.108.023518

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