arXiv 0803.11282008-03-07quant-ph

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

Mathias Michel, Ortwin Hess, Hannu Wichterich, Jochen Gemmer

备注：: to be published in Physical Reviews B
发表信息：: Phys. Rev. B 77, 104303 (2008)
DOI：: 10.1103/PhysRevB.77.104303

英文摘要：

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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