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arXiv · 1707.01791

Odd-triplet superconductivity in single-level quantum dots

S. Weiss·J. König
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Abstract

We study the interplay of spin and charge coherence in a single-level quantum dot. A tunnel coupling to a superconducting lead induces superconducting correlations in the dot. With full spin symmetry retained, only even-singlet superconducting correlations are generated. An applied magnetic field or attached ferromagnetic leads partially or fully reduce the spin symmetry, and odd-triplet superconducting correlations are generated as well. For single-level quantum dots, no other superconducting correlations are possible. We analyze, with the help of a diagrammatic real-time technique, the interplay of spin symmetry and superconductivity and its signatures in electronic transport, in particular current and shot noise.

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S. Weiss, J. König. 2017-07-06. Odd-triplet superconductivity in single-level quantum dots. https://doi.org/10.1103/physrevb.96.064529

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