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Nonlinear transport through a finite Hubbard chain connected to the electrodes

Kamil Walczak
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Abstract

Coherent electronic transport through a molecular device is studied using non-equilibrium Green's function (NEGF) formalism. Such device is made of a short linear wire which is connected to para- and ferromagnetic electrodes. Molecule itself is described with the help of Huckel (tight-binding) model with the electron interactions treated within Hubbard approach, while the coupling to the electrodes is modeled through the use of a broad-band theory. Coulomb interactions within molecular wire are treated by means of the Hartree-Fock (HF) approximation. For the case of asymmetric coupling to paramagnetic electrodes, charging-induced rectification effect in biased molecular devices is discussed as a consequence of Coulomb repulsion. For the system with ferromagnetic electrodes, a significant magnetoresistance (MR) is predicted and its oscillations generated by Coulomb interactions are considered.

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Kamil Walczak. 2004-11-16. Nonlinear transport through a finite Hubbard chain connected to the electrodes. https://doi.org/10.1016/j.physb.2005.05.014

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