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arXiv · 0903.2007

Critical Josephson current through a bistable single-molecule junction

Andreas Schulz·Alex Zazunov·Reinhold Egger
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Abstract

We compute the critical Josephson current through a single-molecule junction. As a model for a molecule with a bistable conformational degree of freedom, we study an interacting single-level quantum dot coupled to a two-level system and weakly connected to two superconducting electrodes. We perform a lowest-order perturbative calculation of the critical current and show that it can significantly change due to the two-level system. In particular, the π-junction behavior, generally present for strong interactions, can be completely suppressed.

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Andreas Schulz, Alex Zazunov, Reinhold Egger. 2009-05-05. Critical Josephson current through a bistable single-molecule junction. https://doi.org/10.1103/physrevb.79.184517

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