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Multistable transport regimes and conformational changes in molecular quantum dots

Alexander O. Gogolin·Andrei Komnik
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Abstract

We analyse non-equilibrium transport properties of a single-state molecular quantum dot coupled to a local phonon and contacted by two electrodes. We derive the effective non-equilibrium (Keldysh) action for the phonon mode and study the structure of the saddle points, which turn out to be symmetric with respect to time inversion. Above a critical electron-phonon coupling lambda_c the effective potential for the phonon mode develops two minima in the equilibrium and three minima in the case of a finite bias voltage. For strongly interacting Luttinger liquid leads lambda_c=0. Some implications for transport experiments on molecular quantum dots are discussed.

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Alexander O. Gogolin, Andrei Komnik. 2002-07-22. Multistable transport regimes and conformational changes in molecular quantum dots. https://arxiv.org/abs/cond-mat/0207513

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