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arXiv · 1203.4128

Experimental Evidence for Quantum Interference and Vibrationally Induced Decoherence in Single-Molecule Junctions

Stefan Ballmann·Rainer Härtle·Pedro B. Coto·Marcel Mayor·Mark Elbing·Martin R. Bryce·Michael Thoss·Heiko B. Weber
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Abstract

We analyze quantum interference and decoherence effects in single-molecule junctions both experimentally and theoretically by means of the mechanically controlled break junction technique and density-functional theory. We consider the case where interference is provided by overlapping quasi-degenerate states. Decoherence mechanisms arising from the electronic-vibrational coupling strongly affect the electrical current flowing through a single-molecule contact and can be controlled by temperature variation. Our findings underline the all-important relevance of vibrations for understanding charge transport through molecular junctions.

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Stefan Ballmann, Rainer Härtle, Pedro B. Coto, Marcel Mayor, Mark Elbing, Martin R. Bryce, Michael Thoss, Heiko B. Weber. 2012-03-19. Experimental Evidence for Quantum Interference and Vibrationally Induced Decoherence in Single-Molecule Junctions. https://doi.org/10.1103/physrevlett.109.056801

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