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arXiv · 1706.07803

Quantum quench of the Sachdev-Ye-Kitaev Model

Andreas Eberlein·Valentin Kasper·Subir Sachdev·Julia Steinberg
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Abstract

We describe the non-equilibrium dynamics of the Sachdev-Ye-Kitaev models of fermions with all-to-all interactions. These provide tractable models of the dynamics of quantum systems without quasiparticle excitations. The Kadanoff-Baym equations show that the final state is thermal, and their numerical analysis appears consistent with a thermalization rate proportional to the absolute temperature of the final state. We also obtain an exact analytic solution of the non-equilibrium dynamics in the large $q$ limit of a model with $q$ fermion interactions: in this limit, the thermalization of the fermion Green's function is instantaneous.

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Andreas Eberlein, Valentin Kasper, Subir Sachdev, Julia Steinberg. 2017-07-11. Quantum quench of the Sachdev-Ye-Kitaev Model. https://doi.org/10.1103/physrevb.96.205123

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