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Vibration-induced Kondo tunneling through metal-organic complexes with even electron occupation number

K. Kikoin·M. N. Kiselev·M. R. Wegewijs
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Abstract

We investigate transport through a mononuclear transition-metal complex with strong tunnel coupling to two electrodes. The ground state of this molecule is a singlet while the first excited state is a triplet. We show that a modulation of the tunnel-barrier due to a molecular distortion which couples to the tunneling induces a Kondo-effect, provided the discrete vibrational energy compensates the singlet/triplet gap. We discuss the single-phonon and two-phonon assisted co-tunneling and possible experimental realization of the theory.

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K. Kikoin, M. N. Kiselev, M. R. Wegewijs. 2005-11-15. Vibration-induced Kondo tunneling through metal-organic complexes with even electron occupation number. https://doi.org/10.1103/physrevlett.96.176801

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