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Dynamical symmetry breaking in transport through molecules

Andrea Donarini·Milena Grifoni·Klaus Richter
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Abstract

We analyze the interplay between vibrational and electronic degrees of freedom in charge transport across a molecular single-electron transistor. We focus on the wide class of molecules which possess quasi-degenerate vibrational eigenstates, while no degeneracy occurs for their anionic configuration. We show that the combined effect of a thermal environment and coupling to leads, involving tunneling events charging and discharging the molecule, leads to a dynamical symmetry breaking where quasi-degenerate eigenstates acquire different occupations. This imbalance gives rise to a characteristic asymmetry of the current versus an applied gate voltage.

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Andrea Donarini, Milena Grifoni, Klaus Richter. 2006-10-17. Dynamical symmetry breaking in transport through molecules. https://doi.org/10.1103/physrevlett.97.166801

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