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arXiv · 2207.01825

Obstructions to odd-frequency superconductivity in Eliashberg theory

Edwin Langmann·Christian Hainzl·Robert Seiringer·Alexander V. Balatsky
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Abstract

We present a necessary condition for odd-frequency (odd-f) superconductivity (SC) to occur in a large class of materials described by Eliashberg theory. We use this condition to prove a no-go theorem ruling out the occurrence of odd-f SC in standard one-band superconductors with pairing interactions mediated by phonon exchange. We also present a corresponding no-go theorem for superconductors with interactions mediated by spin-fluctuations. Our results explain why odd-f SC is rare in conventional materials, and they open up the possibility for a search for materials with interactions designed so as to allow for odd-f SC.

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Edwin Langmann, Christian Hainzl, Robert Seiringer, Alexander V. Balatsky. 2022-07-05. Obstructions to odd-frequency superconductivity in Eliashberg theory. https://arxiv.org/abs/2207.01825

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