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arXiv · 0803.1128

Transport in open spin chains: A Monte Carlo wave-function approach

Mathias Michel·Ortwin Hess·Hannu Wichterich·Jochen Gemmer
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Abstract

We investigate energy transport in several two-level atom or spin-1/2 models by a direct coupling to heat baths of different temperatures. The analysis is carried out on the basis of a recently derived quantum master equation which describes the nonequilibrium properties of internally weakly coupled systems appropriately. For the computation of the stationary state of the dynamical equations, we employ a Monte Carlo wave-function approach. The analysis directly indicates normal diffusive or ballistic transport in finite models and hints toward an extrapolation of the transport behavior of infinite models.

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Mathias Michel, Ortwin Hess, Hannu Wichterich, Jochen Gemmer. 2008-03-07. Transport in open spin chains: A Monte Carlo wave-function approach. https://doi.org/10.1103/physrevb.77.104303

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