arXiv:1306.4986 · Physical Review Letters

Dynamics of Thermalization and Decoherence of a Nanoscale System

Sam Genway, A. F. Ho, Derek K. K. Lee

Published Sep 26, 2013• 25 citations

Abstract

We study the decoherence and thermalization dynamics of a nanoscale system coupled nonperturbatively to a fully quantum-mechanical bath. The system is prepared out of equilibrium in a pure state of the complete system. We propose a random matrix model and show analytically that there are two robust temporal regimes in the approach of the system to equilibrium-an initial Gaussian decay followed by an exponential tail, consistent with numerical results on small interacting lattices [S. Genway, A. F. Ho, and D. K. K. Lee, Phys. Rev. Lett. 105, 260402 (2010)]. Furthermore, the system decays towards a Gibbs ensemble in accordance with the eigenstate thermalization hypothesis.

DOI: 10.1103/physrevlett.111.130408

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