Quantum Dot between two Superconductors

Yshai Avishai; Anatoly Golub; Andrei D. Zaikin

doi:10.1209/epl/i2001-00340-1

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Quantum Dot between two Superconductors

Yshai Avishai·Anatoly Golub·Andrei D. Zaikin

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Abstract

Novel effects emerge from an interplay between multiple Andreev reflections and Coulomb interaction in quantum dot coupled to superconducting leads and subject to a finite potential bias $V$. Combining an intuitive physical picture with rigorous path integral formalism we evaluate the current $I$ through the dot and find that the interaction shifts the subharmonic pattern of the $I-V$ curve is shifted toward higher $V$. For sufficiently ^M strong interaction the subgap current (at $eV < 2 Δ$) is virtually suppressed.

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Yshai Avishai, Anatoly Golub, Andrei D. Zaikin. 2000-07-06. Quantum Dot between two Superconductors. https://doi.org/10.1209/epl%2Fi2001-00340-1

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