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arXiv · 1405.1337

Current Noise in Single-Molecule Junctions Induced by Electronic-Vibrational Coupling

C. Schinabeck·R. Härtle·H. B. Weber·M. Thoss
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Abstract

The influence of multiple vibrational modes on current fluctuations in electron transport through single-molecule junctions is investigated. Our analysis is based on a generic model of a molecular junction, which comprises a single electronic state on the molecular bridge coupled to multiple vibrational modes and fermionic leads, and employs a master equation approach. The results reveal that in molecular junctions with multiple vibrational modes already weak to moderate electronic-vibrational coupling may result in high noise levels, especially at the onset of resonant transport, in accordance with experimental findings of Secker et al..[1] The underlying mechanisms are analyzed in some detail. [1] D. Secker et al., Phys. Rev. Lett. 106, 136807 (2011).

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C. Schinabeck, R. Härtle, H. B. Weber, M. Thoss. 2014-05-06. Current Noise in Single-Molecule Junctions Induced by Electronic-Vibrational Coupling. https://doi.org/10.1103/physrevb.90.075409

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