DFT-based calculation of Coulomb blockade in molecular junction

Bo Song

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arXiv · 0710.0475

DFT-based calculation of Coulomb blockade in molecular junction

Bo Song

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Abstract

Quantum transport through single molecules is very sensitive to the strength of the molecule-electrode contact. When a molecular junction weakly coupled to external electrodes, charging effects do play an important role (Coulomb blockade regime). In this regime, the non-equilibrium Green function is usually substituted with master equation approaches, which prevents the density functional theory from describing Coulomb blockade in non-equilibrium case. Last year, we proposed an Ansatz to combine the non-equilibrium Green function technique with the equation of motion method. With help of it, Coulomb blockade was obtained by non-equilibrium Green function, and completely agrees with the master equation results [Phys. Rev. B \textbf{76}, 045408 (2007)]. Here, by the Ansatz, we show a new way to introduce Coulomb blockade correction to DFT calculation in non-equilibrium case. And the characteristics of Coulomb blockade are obtained in the calculation of a $toy$ molecule correctly.

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Bo Song. 2007-10-02. DFT-based calculation of Coulomb blockade in molecular junction. https://arxiv.org/abs/0710.0475

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