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arXiv:1706.07803 · Physical review. B./Physical review. B

Quantum quench of the Sachdev-Ye-Kitaev model

Andreas Eberlein, Valentin Kasper, Subir Sachdev A, Julia Steinberg

Published Nov 14, 2017• 145 citations
arXivHTMLPDF

Abstract

We describe the nonequilibrium quench dynamics of the Sachdev-Ye-Kitaev models of fermions with random all-to-all interactions. These provide tractable models of the dynamics of quantum systems without quasiparticle excitations. The Kadanoff-Baym equations show that, at long times, the fermion two-point function has a thermal form at a final temperature determined by energy conservation, and the numerical analysis is consistent with a thermalization rate proportional to this temperature. We also obtain an exact analytic solution of the quench dynamics in the large $q$ limit of a model with $q$ fermion interactions: in this limit, the thermalization of the two-point function is instantaneous.

DOI
10.1103/physrevb.96.205123

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