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arXiv · 2306.03017

Controllable odd-frequency Cooper pairs in multi-superconductor Josephson junctions

Jorge Cayao·Pablo Burset·Yukio Tanaka
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Abstract

We consider Josephson junctions formed by multiple superconductors with distinct phases and explore the formation of nonlocal or inter-superconductor pair correlations. We find that the multiple superconductor nature offers an additional degree of freedom that broadens the classification of pair symmetries, enabling nonlocal even- and odd-frequency pairings that can be highly controlled by the superconducting phases and the energy of the superconductors. Specially, when the phase difference between two superconductors is $\pi$, their associated nonlocal odd-frequency pairing is the only type of inter-superconductor pair correlations. Finally, we show that these nonlocal odd-frequency Cooper pairs dominate the nonlocal conductance via crossed Andreev reflections, which constitutes a direct evidence of odd-frequency pairing.

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Jorge Cayao, Pablo Burset, Yukio Tanaka. 2023-06-05. Controllable odd-frequency Cooper pairs in multi-superconductor Josephson junctions. https://doi.org/10.1103/physrevb.109.205406

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