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arXiv:0808.0589 · Physical Review B

Real-time diagrammatic Monte Carlo for nonequilibrium quantum transport

Marco Schirò, Michele Fabrizio

Published Apr 13, 2009• 170 citations
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Abstract

We propose a numerically exact approach to nonequilibrium real-time dynamics that is applicable to quantum impurity models coupled to biased noninteracting leads, such as those relevant to quantum transport in nanoscale devices. The method is based on a diagrammatic Monte Carlo sampling of the real-time perturbation theory along the Keldysh contour. We benchmark the method on a noninteracting resonant-level model and, as a first nontrivial application, we study zero-temperature nonequilibrium transport through a vibrating molecule.

DOI
10.1103/physrevb.79.153302

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