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arXiv · 2506.16907

Josephson wormhole in coupled superconducting Yukawa-SYK metals

Aravindh S. Shankar·Jasper Steenbergen·Stephan Plugge·Koenraad Schalm
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Abstract

We show that two Yukawa-SYK models with a weak tunneling contact can have an exotic hybrid superconducting thermofield-double-like state that is holographically dual to a traversable wormhole connecting two black holes with charged scalar hair. The hybrid superconducting thermo-field-double/wormhole state is distinguishable by anomalous scaling of revival oscillations in the fermionic Green's function, but also in a unique Andreev-revival in the anomalous Green's function. The existence of this TFD/wormhole state surprisingly shows that the some quantum critical effects can survive the phase transition to superconductivity. This Andreev-revival is in principle an accessible signature of the transition to the TFD/wormhole phase detectable in the ac-Josephson current.

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Aravindh S. Shankar, Jasper Steenbergen, Stephan Plugge, Koenraad Schalm. 2025-06-20. Josephson wormhole in coupled superconducting Yukawa-SYK metals. https://doi.org/10.1103/v2gn-l936

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