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arXiv · 1405.5515

Numerical Study of a Many-Body Localized System Coupled to a Bath

Sonika Johri·Rahul Nandkishore·R. N. Bhatt
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Abstract

We use exact diagonalization to study the breakdown of many-body localization in a strongly disordered and interacting system coupled to a thermalizing environment. We show that the many-body level statistics cross over from Poisson to GOE, and the localized eigenstates thermalize, with the crossover coupling decreasing with the size of the bath in a manner consistent with the hypothesis that an infinitesimally small coupling to a thermodynamic bath should destroy localization of the eigenstates. However, signatures of incomplete localization survive in spectral functions of local operators even when the coupling to the environment is non-zero. These include a discrete spectrum and a gap at zero frequency. Both features are washed out by line broadening as one increases the coupling to the bath.

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Sonika Johri, Rahul Nandkishore, R. N. Bhatt. 2014-10-27. Numerical Study of a Many-Body Localized System Coupled to a Bath. https://arxiv.org/abs/1405.5515

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