Inelastic effects in molecular junctions in the Coulomb and Kondo regimes: Nonequilibrium equation-of-motion approach

Inelastic effects in the Coulomb blockade and Kondo regimes of electron transport through molecular junctions are considered within a simple nonequilibrium equation-of-motion (EOM) approach. The scheme is self-consistent and can qualitatively reproduce the main experimental observations of vibrational features in the Coulomb blockade [ H. Park et al. Nature (London) 407 57 (2000)] and Kondo [ L. H. Yu et al. Phys. Rev. Lett. 93 266802 (2004)] regimes. Considerations similar to the equilibrium EOM approach by Meir et al. Phys. Rev. Lett. 66 3048 (1991) 70 2601 (1993) are used on the Keldysh contour to account for the nonequilibrium nature of the junction, and dressing by appropriate Franck-Condon factors is used to account for vibrational features. Results of the equilibrium EOM scheme by Meir et al. are reproduced in the appropriate limit.