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arXiv:2112.08158 · SciPost Physics

Multiple relaxation times in perturbed XXZ chain

Marcin Mierzejewski, Jakub Pawłowski, Peter Prelovšek, J. Herbrych

Published Aug 5, 2022• 10 citations
arXivHTMLPDF

Abstract

We numerically study the relaxation of correlation functions in weakly perturbed integrable XXZ chain. The decay of the spin-current and the energy-current correlations at zero magnetization are well described by single, but quite distinct, relaxation rates governed by the square of the perturbation strength g g . However, at finite magnetization a single correlation function reveals multiple relaxation rates. The result can be understood in terms of multi-scale relaxation scenario, where various relaxation times are linked with various quantities which are conserved in the reference integrable system. On the other hand, the correlations of non-commuting quantities, being conserved at particular anisotropies \Delta Δ , decay non-exponentially with characteristic time scale linear in g g .

DOI
10.21468/scipostphys.13.2.013

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