Quantum quench dynamics of the sine-Gordon model in some solvable limits

TL;DR

This paper analytically studies the non-thermalizing dynamics of the sine-Gordon model after quantum quenches in solvable limits, highlighting the role of integrability and generalized Gibbs ensembles.

Contribution

It provides explicit analytic expressions for correlation functions post-quench in the sine-Gordon model's solvable limits, elucidating integrability effects on thermalization.

Findings

Correlations are described by a generalized Gibbs ensemble at long times.

The model exhibits non-thermalizing behavior due to integrability.

Finite temperature initial states influence the post-quench dynamics.

Abstract

In connection with the the thermalization problem in isolated quantum systems, we investigate the dynamics following a quantum quench of the sine-Gordon model in the Luther-Emery and the semiclassical limits. We consider the quench from the gapped to the gapless phase as well as reversed one. By obtaining analytic expressions for the one and two-point correlation functions of the order parameter operator at zero-temperature, the manifestations of integrability in the absence of thermalization in the sine-Gordon model are studied. It is thus shown that correlations in the long time regime after the quench are well described by a generalized Gibbs ensemble. We also consider the case where the system is initially in contact with a reservoir at finite temperature. The possible relevance of our results to current and future experiments with ultracold atomic systems is also critically considered.