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arXiv · 2107.04445

Exceptional odd-frequency pairing in non-Hermitian superconducting systems

Jorge Cayao·Annica M. Black-Schaffer
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Abstract

We first show the realization of exceptional points in a non-Hermitian superconducting system based on a conventional superconductor and then demonstrate that, surprisingly, the system hosts odd-frequency pairing, solely generated by the non-Hermiticity. While there is a coexistence of even- and odd-frequency pairs under general conditions, we find that the even-frequency term vanishes at the exceptional degeneracies, leaving only odd-frequency pairing. This exceptional odd-frequency pairing is directly given by the imaginary part of the eigenvalues at the exceptional points and can be measured from the spectral function. Our results thus put forward non-Hermitian systems as a powerful platform to realize odd-frequency superconducting pairing.

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Jorge Cayao, Annica M. Black-Schaffer. 2021-07-09. Exceptional odd-frequency pairing in non-Hermitian superconducting systems. https://doi.org/10.1103/physrevb.105.094502

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