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arXiv · 2108.10796

Markovian baths and quantum avalanches

Dries Sels
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Abstract

In this work I will discuss some numerical results on the stability of the many-body localized phase to thermal inclusions. The work simplifies a recent proposal by Morningstar et al. [arXiv:2107.05642] and studies small disordered spin chains which are perturbatively coupled to a Markovian bath. The critical disorder for avalanche stability of the canonical disordered Heisenberg chain is shown to exceed W>20. In stark contrast to the Anderson insulator, the avalanche threshold drifts considerably with system size, with no evidence of saturation in the studied regime. I will argue that the results are most easily explained by the absence of a many-body localized phase.

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Dries Sels. 2021-08-24. Markovian baths and quantum avalanches. https://doi.org/10.1103/physrevb.106.l020202

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