1108.0270 (C. Ates et al.)

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

C. Ates, J. P. Garrahan, I. Lesanovsky

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.

View original: http://arxiv.org/abs/1108.0270