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arXiv · 1102.0840

Vibrational Instabilities in Resonant Electron Transport through Single-Molecule Junctions

R. Härtle·M. Thoss
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Abstract

We analyze various limits of vibrationally coupled resonant electron transport in single-molecule junctions. Based on a master equation approach, we discuss analytic and numerical results for junctions under a high bias voltage or weak electronic-vibrational coupling. It is shown that in these limits the vibrational excitation of the molecular bridge increases indefinitely, i.e. the junction exhibits a vibrational instability. Moreover, our analysis provides analytic results for the vibrational distribution function and reveals that these vibrational instabilities are related to electron-hole pair creation processes.

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R. Härtle, M. Thoss. 2011-02-04. Vibrational Instabilities in Resonant Electron Transport through Single-Molecule Junctions. https://doi.org/10.1103/physrevb.83.125419

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