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arXiv · 1102.4190

Quantum Interference and Decoherence in Single-Molecule Junctions: How Vibrations Induce Electrical Current

R. Härtle·M. Butzin·O. Rubio-Pons·M. Thoss
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Abstract

Quantum interference effects and decoherence mechanisms in single-molecule junctions are analyzed employing a nonequilibrium Green's function approach. Electrons tunneling through quasi-degenerate states of a nanoscale molecular junction exhibit interference effects. We show that electronic-vibrational coupling, inherent to any molecular junction, strongly quenches such interference effects. As a result, the electrical current can be significantly larger than without electronic-vibrational coupling. The analysis reveals that the quenching of quantum interference is particularly pronounced if the junction is vibrationally highly excited, e.g. due to current-induced nonequilibrium effects in the resonant transport regime.

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R. Härtle, M. Butzin, O. Rubio-Pons, M. Thoss. 2011-02-21. Quantum Interference and Decoherence in Single-Molecule Junctions: How Vibrations Induce Electrical Current. https://doi.org/10.1103/physrevlett.107.046802

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