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arXiv · 2005.13546

Hydrodynamics of nonintegrable systems from a relaxation-time approximation

Javier Lopez-Piqueres·Brayden Ware·Sarang Gopalakrishnan·Romain Vasseur
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Abstract

We develop a general kinetic theory framework to describe the hydrodynamics of strongly interacting, nonequilibrium quantum systems in which integrability is weakly broken, leaving a few residual conserved quantities. This framework is based on a generalized relaxation-time approximation; it gives a simple, but surprisingly accurate, prescription for computing nonequilibrium transport even in strongly interacting systems. This approximation reproduces the crossover from generalized to conventional hydrodynamics in interacting one-dimensional Bose gases with integrability-breaking perturbations, both with and without momentum conservation. It also predicts the hydrodynamics of chaotic quantum spin chains, in good agreement with matrix product operator calculations.

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BibTeXRIS

Javier Lopez-Piqueres, Brayden Ware, Sarang Gopalakrishnan, Romain Vasseur. 2020-05-27. Hydrodynamics of nonintegrable systems from a relaxation-time approximation. https://doi.org/10.1103/physrevb.103.l060302

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