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arXiv · 1009.5312

DFT-based many-body analysis of electron transport through molecules

Fatemeh Mirjani·Joseph M. Thijssen
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Abstract

We present a method which uses density functional theory (DFT) to treat transport through a single molecule connected to two conducting leads for the weak and intermediate coupling. This case is not accessible to standard non-equilibrium Green's function (NEGF) calculations. Our method is based on a mapping of the Hamiltonian on the molecule to a limited set of many-body eigenstates. This generates a many-body Hamiltonian with parameters obtained from ground state L(S)DA-DFT calculations. We then calculate the transport using many-body Green's function theory. We compare our results with existing density matrix renormalization group (DMRG) calculations for spinless and for spin-1/2 fermion chains and find good agreement.

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Fatemeh Mirjani, Joseph M. Thijssen. 2011-01-20. DFT-based many-body analysis of electron transport through molecules. https://doi.org/10.1103/physrevb.83.035415

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