Nonequilibrium diagrammatic technique for Hubbard Green functions

Feng Chen; Maicol A. Ochoa; Michael Galperin

doi:10.1063/1.4965825

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arXiv · 1610.00036

Nonequilibrium diagrammatic technique for Hubbard Green functions

Feng Chen·Maicol A. Ochoa·Michael Galperin

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Abstract

We introduce diagrammatic technique for Hubbard nonequilibrium Green functions (NEGF). The formulation is an extension of equilibrium considerations for strongly correlated lattice models to description of current carrying molecular junctions. Within the technique intra-system interactions are taken into account exactly, while molecular coupling to contacts is used as a small parameter in perturbative expansion. We demonstrate the viability of the approach with numerical simulations for a generic junction model of quantum dot coupled to two electron reservoirs.

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Feng Chen, Maicol A. Ochoa, Michael Galperin. 2016-09-30. Nonequilibrium diagrammatic technique for Hubbard Green functions. https://doi.org/10.1063/1.4965825

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