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arXiv · 0802.3326

Transport signature of pseudo-Jahn-Teller dynamics in a single-molecule transistor

F. Reckermann·M. Leijnse·M. R. Wegewijs·H. Schoeller
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Abstract

We calculate the electronic transport through a molecular dimer, in which an excess electron is delocalized over equivalent monomers, which can be locally distorted. In this system the Born-Oppenheimer approximation breaks down resulting in quantum entanglement of the mechanical and electronic motion. We show that pseudo Jahn-Teller (pJT) dynamics of the molecule gives rise to conductance peaks that indicate this violation. Their magnitude, sign and position sharply depend on the electro-mechanical properties of the molecule, which can be varied in recently developed three-terminal junctions with mechanical control. The predicted effect depends crucially on the degree of intramolecular delocalization of the excess electron, a parameter which is also of fundamental importance in physical chemistry.

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F. Reckermann, M. Leijnse, M. R. Wegewijs, H. Schoeller. 2009-03-11. Transport signature of pseudo-Jahn-Teller dynamics in a single-molecule transistor. https://doi.org/10.1209/0295-5075%2F83%2F58001

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