arXiv 0801.26692008-01-17quant-phcond-mat.mes-hallcond-mat.stat-mech

Transport in anisotropic model systems analyzed by a correlated projection superoperator technique

Hendrik Weimer, Mathias Michel, Jochen Gemmer, Günter Mahler

备注：: 8 pages, 6 figures
发表信息：: Phys. Rev. E 77, 011118 (2008)
DOI：: 10.1103/PhysRevE.77.011118

英文摘要：

By using a correlated projection operator, the time-convolutionless (TCL) method to derive a quantum master equation can be utilized to investigate the transport behavior of quantum systems as well. Here, we analyze a three-dimensional anisotropic quantum model system according to this technique. The system consists of Heisenberg coupled two-level systems in one direction and weak random interactions in all other ones. Depending on the partition chosen, we obtain ballistic behavior along the chains and normal transport in the perpendicular direction. These results are perfectly confirmed by the numerical solution of the full time-dependent Schrödinger equation.

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