Dynamical symmetry breaking in vibration-assisted transport through nanostructures

Abstract

A theoretical model of a single molecule coupled to many vibronic modes is presented. At low energies, transport is dominated by electron-vibron processes where transfer of an electron through the dot is accompanied by the excitation/emission of quanta (vibrons). Because the frequency of the $n$th mode is taken as an $n$th multiple of the frequency of the fundamental mode, several energetically degenerate or quasi-degenerate vibronic configurations can contribute to transport. We investigate the consequences of strong electron-vibron coupling in a fully \emph{symmetric} set-up. Several striking features are predicted. In particular, a gate-asymmetry and pronounced negative differential conductance features are observed. We attribute these features to the presence of slow channels originating from the interplay of Franck-Condon suppression of transport channels and spin/orbital degeneracies.

10 pages, 11 figures, published version

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Cited by in corpus (9)

• Microwave quantum optics and electron transport through a metallic dot strongly coupled to a transmission line cavity
• Charge-vibration interaction effects in normal-superconductor quantum dots
• Vibration-assisted exciton transfer in molecular aggregates strongly coupled to confined light fields
• Finite frequency current noise in the Holstein model
• Spectrum and Franck-Condon factors of interacting suspended single-wall carbon nanotubes
• Vibration induced memory effects and switching in ac-driven molecular nanojunctions
• Magnetic field control of the Franck-Condon coupling of few-electron quantum states
• Vibrational assisted conduction in a molecular wire
• Interference and shot noise in a degenerate Anderson-Holstein model