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arXiv · 1904.03147

Quantum quenches in isolated quantum glasses out of equilibrium

S. J. Thomson·P. Urbani·M. Schiro
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Abstract

In this work, we address the question of how a closed quantum system thermalises in the presence of a random external potential. By investigating the quench dynamics of the isolated quantum spherical $p$-spin model, a paradigmatic model of a mean-field glass, we aim to shed new light on this complex problem. Employing a closed-time Schwinger-Keldysh path integral formalism, we first initialise the system in a random, infinite-temperature configuration and allow it to equilibrate in contact with a thermal bath before switching off the bath and performing a quench. We find evidence that increasing the strength of either the interactions or the quantum fluctuations can act to lower the effective temperature of the isolated system and stabilise glassy behaviour.

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S. J. Thomson, P. Urbani, M. Schiro. 2020-09-22. Quantum quenches in isolated quantum glasses out of equilibrium. https://doi.org/10.1103/physrevlett.125.120602

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