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arXiv · 2105.13968

Observation of Anomalous Josephson Effect in Nonequilibrium Andreev Interferometers

D. Margineda·J. S. Claydon·F. Qejvanaj·C. Checkley
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Abstract

The first evidence of anomalous Josephson effect is reported in mesoscopic superconductor-normal metal-superconductor (SNS) junctions forming a crosslike Andreev Interferometer in the absence of magnetic and spin-orbit interactions normally required to break time-reversal and inversion symmetries. From conductance measurements of the out-of-equilibrium weak link, we determine a voltage-controlled spontaneous phase that resembles a $\varphi_0$-junction. The temperature and voltage dependences together with a dissipative term in the current-phase relation strongly suggest that the mechanism underlying the observed phenomenon relies on electron-hole asymmetries.

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D. Margineda, J. S. Claydon, F. Qejvanaj, C. Checkley. 2021-05-28. Observation of Anomalous Josephson Effect in Nonequilibrium Andreev Interferometers. https://doi.org/10.1103/physrevb.107.l100502

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