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arXiv · 0906.4738

Transient dynamics of a molecular quantum dot with a vibrational degree of freedom

R. -P. Riwar·T. L. Schmidt
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Abstract

We investigate the transient effects occurring in a molecular quantum dot described by an Anderson-Holstein Hamiltonian which is instantly coupled to two fermionic leads biased by a finite voltage. In the limit of weak electron-phonon interaction, we use perturbation theory to determine the time-dependence of the dot population and the average current. The limit of strong coupling is accessed by means of a self-consistent time-dependent mean-field approximation. These comple- mentary approaches allow us to investigate the dynamics of the inelastic effects occurring when the applied bias voltage exceeds the phonon frequency and the emergence of bistability.

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R. -P. Riwar, T. L. Schmidt. 2009-06-25. Transient dynamics of a molecular quantum dot with a vibrational degree of freedom. https://doi.org/10.1103/physrevb.80.125109

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