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arXiv · 1506.05653

Pulling and Stretching a Molecular Wire to Tune its Conductance

Gaël Reecht·Hervé Bulou·Fabrice Scheurer·Virginie Speisser·Fabrice Mathevet·César González·Yannick J. Dappe·Guillaume Schull
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Abstract

A scanning tunnelling microscope is used to pull a polythiophene wire from a Au(111) surface while measuring the current traversing the junction. Abrupt current increases measured during the lifting procedure are associated to the detachment of molecular sub-units, in apparent contradiction with the expected exponential decrease of the conductance with wire length. \textit{Ab initio} simulations reproduce the experimental data and demonstrate that this unexpected behavior is due to release of mechanical stress in the wire, paving the way to mechanically gated single-molecule electronic devices.

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Gaël Reecht, Hervé Bulou, Fabrice Scheurer, Virginie Speisser, Fabrice Mathevet, César González, Yannick J. Dappe, Guillaume Schull. 2015-08-05. Pulling and Stretching a Molecular Wire to Tune its Conductance. https://doi.org/10.1021/acs.jpclett.5b01283

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