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arXiv · 1904.02202

Chaos based Berry phase detector

Cheng-Zhen Wang·Chen-Di Han·Hong-Ya Xu·Ying-Cheng Lai
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Abstract

The geometric or Berry phase, a characteristic of quasiparticles, is fundamental to the underlying quantum materials. The discoveries of new materials at a rapid pace nowadays call for efficient detection of the Berry phase. Utilizing $α$-T$_3$ lattice as a paradigm, we find that, in the Dirac electron optics regime, the semiclassical decay of the quasiparticles from a chaotic cavity can be effectively exploited for detecting the Berry phase. In particular, we demonstrate a one-to-one correspondence between the exponential decay rate and the geometric phase for the entire family of $α$-T$_3$ materials. This chaos based detection scheme represents an experimentally feasible way to assess the Berry phase and to distinguish the quasiparticles.

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Cheng-Zhen Wang, Chen-Di Han, Hong-Ya Xu, Ying-Cheng Lai. 2019-04-03. Chaos based Berry phase detector. https://doi.org/10.1103/physrevb.99.144302

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