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arXiv · 1711.01740

Semiclassical theory of strong localization for quantum thermalization

Christine Khripkov·Amichay Vardi·Doron Cohen
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Abstract

We introduce a semiclassical theory for strong localization that may arise in the context of many-body thermalization. As a minimal model for thermalization we consider a few-site Bose-Hubbard model consisting of two weakly interacting subsystems that can exchange particles. The occupation of a subsystem ($x$) satisfies in the classical treatment a Fokker-Planck equation with a diffusion coefficient $D(x)$. We demonstrate that it is possible to deduce from the classical description a quantum breaktime $t^*$, and hence the manifestations of a strong localization effect. For this purpose it is essential to take the geometry of the energy shell into account, and to make a distinction between different notions of phasespace exploration.

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Christine Khripkov, Amichay Vardi, Doron Cohen. 2018-02-18. Semiclassical theory of strong localization for quantum thermalization. https://doi.org/10.1103/physreve.97.022127

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