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arXiv · 2004.11030

Non-Equilibrium Dynamics and Weakly Broken Integrability

Joseph Durnin·M. J. Bhaseen·Benjamin Doyon
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Abstract

Motivated by dynamical experiments on cold atomic gases, we develop a quantum kinetic approach to weakly perturbed integrable models out of equilibrium. Using the exact matrix elements of the underlying integrable model we establish an analytical approach to real-time dynamics. The method addresses a broad range of timescales, from the intermediate regime of pre-thermalization to late-time thermalization. Predictions are given for the time-evolution of physical quantities, including effective temperatures and thermalization rates. The approach provides conceptual links between perturbed quantum many-body dynamics and classical Kolmogorov-Arnold-Moser (KAM) theory. In particular, we identify a family of perturbations which do not cause thermalization in the weakly perturbed regime.

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BibTeXRIS

Joseph Durnin, M. J. Bhaseen, Benjamin Doyon. 2021-09-01. Non-Equilibrium Dynamics and Weakly Broken Integrability. https://doi.org/10.1103/physrevlett.127.130601

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