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arXiv · 1304.6919

Iterative path integral summation for nonequilibrium quantum transport

S. Weiss·R. Hützen·D. Becker·J. Eckel·R. Egger·M. Thorwart
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Abstract

We have developed a numerically exact approach to compute real-time path integral expressions for quantum transport problems out of equilibrium. The scheme is based on a deterministic iterative summation of the path integral (ISPI) for the generating function of nonequilibrium observables of interest, e.g., the charge current or dynamical quantities of the central part. Self-energies due to the leads, being nonlocal in time, are fully taken into account within a finite memory time, thereby including non-Markovian effects. Numerical results are extra-polated first to vanishing (Trotter) time discretization and, second, to infinite memory time...

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S. Weiss, R. Hützen, D. Becker, J. Eckel, R. Egger, M. Thorwart. 2013-04-25. Iterative path integral summation for nonequilibrium quantum transport. https://doi.org/10.1002/pssb.201349187

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