Proceedings of the Royal Society A Mathematical Physical and Engineering Sciences

Mean-field evolution of open quantum systems: an exactly solvable model

Marco Merkli, G. P. Berman

Published Jul 4, 2012• 13 citations

Abstract

We consider quantum particles coupled to local and collective thermal quantum environments. The coupling is energy conserving, and the collective coupling is scaled in the mean-field way. There is no direct interaction between the particles. We show that an initially factorized state of the particles remains factorized at all times, in the limit of large particle number. Each single-particle factor evolves according to an explicit, nonlinear, dissipative and time-dependent Hartree–Lindblad equation. The model is exactly solvable; we do not make any weak coupling or any Markovian approximations, and our results are mathematically rigorous.

DOI: 10.1098/rspa.2012.0327

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