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A wave function based ab initio non-equilibrium Green's function approach to charge transport

Martin Albrecht·Bo Song·Alexander Schnurpfeil
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Abstract

We present a novel ab initio non-equilibrium approach to calculate the current across a molecular junction. The method rests on a wave function based description of the central region of the junction combined with a tight binding approximation for the electrodes in the frame of the Keldysh Green's function formalism. In addition we present an extension so as to include effects of the two-particle propagator. Our procedure is demonstrated for a dithiolbenzene molecule between silver electrodes. The full current-voltage characteristic is calculated. Specific conclusions for the contribution of correlation and two-particle effects are derived. The latter are found to contribute about 5% to the current. The order of magnitude of the current coincides with experiments.

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Martin Albrecht, Bo Song, Alexander Schnurpfeil. 2005-12-21. A wave function based ab initio non-equilibrium Green's function approach to charge transport. https://doi.org/10.1063/1.2208297

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