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arXiv · 1108.0270

Thermalization of a strongly interacting closed spin system: From coherent many-body dynamics to a Fokker-Planck equation

C. Ates·J. P. Garrahan·I. Lesanovsky
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Abstract

Thermalization has been shown to occur in a number of closed quantum many-body systems, but the description of the actual thermalization dynamics is prohibitively complex. Here, we present a model - in one and two dimensions - for which we can analytically show that the evolution into thermal equilibrium is governed by a Fokker-Planck equation derived from the underlying quantum dynamics. Our approach does not rely on a formal distinction of weakly coupled bath and system degrees of freedom. The results show that transitions within narrow energy shells lead to a dynamics which is dominated by entropy and establishes detailed balance conditions that determine both the eventual equilibrium state and the non-equilibrium relaxation to it.

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C. Ates, J. P. Garrahan, I. Lesanovsky. 2011-08-01. Thermalization of a strongly interacting closed spin system: From coherent many-body dynamics to a Fokker-Planck equation. https://doi.org/10.1103/physrevlett.108.110603

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