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arXiv · 1101.4440

Effects of coupling to vibrational modes on the ac conductance of molecular junctions

A. Ueda·O. Entin-Wohlman·A. Aharony
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Abstract

We theoretically examine the effect of the coupling of the transport electrons to a vibrational mode of the molecule on the ac linear-response conductance of molecular junctions. Representing the molecule by a single electronic state, we find that at very low temperatures the frequency-dependent conductance is mainly enhanced (suppressed) by the electron-vibration interaction when the chemical potential is below (above) the energy of that state. The vertex corrections of the electron-vibration interaction induce an additional peak structure in the conductance, which can be observed by tuning the tunnel couplings with the leads.

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A. Ueda, O. Entin-Wohlman, A. Aharony. 2011-01-24. Effects of coupling to vibrational modes on the ac conductance of molecular junctions. https://doi.org/10.1103/physrevb.83.155438

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