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arXiv · 2110.13158

Random matrix theory for quantum and classical metastability in local Liouvillians

Jimin L. Li·Dominic C. Rose·Juan P. Garrahan·David J. Luitz
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Abstract

We consider the effects of strong dissipation in quantum systems with a notion of locality, which induces a hierarchy of many-body relaxation timescales as shown in [Phys. Rev. Lett. 124, 100604 (2020)]. If the strength of the dissipation varies strongly in the system, additional separations of timescales can emerge, inducing a manifold of metastable states, to which observables relax first, before relaxing to the steady state. Our simple model, involving one or two "good" qubits with dissipation reduced by a factor $\alpha<1$ compared to the other "bad" qubits, confirms this picture and admits a perturbative treatment.

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Jimin L. Li, Dominic C. Rose, Juan P. Garrahan, David J. Luitz. 2021-10-25. Random matrix theory for quantum and classical metastability in local Liouvillians. https://doi.org/10.1103/physrevb.105.l180201

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