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arXiv · 2201.00831

Universal Josephson diode effect

Margarita Davydova·Saranesh Prembabu·Liang Fu
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Abstract

We propose a universal mechanism for the Josephson diode effect in short Josephson junctions. The proposed mechanism is due to finite Cooper pair momentum and is a manifestation of simultaneous breaking of inversion and time-reversal symmetries. The diode efficiency is up to 40%, which corresponds to an asymmetry between the critical currents in opposite directions $I_{c+}/I_{c-} \approx$ 230%. We show that this arises from both the Doppler shift of the Andreev bound state energies and the phase-independent asymmetric current from the continuum. Finally, we propose a simple scheme for achieving finite-momentum pairing, which does not rely on spin-orbit coupling and thus greatly expands existing platforms for the observation of supercurrent diode effects.

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Margarita Davydova, Saranesh Prembabu, Liang Fu. 2022-01-03. Universal Josephson diode effect. https://doi.org/10.1126/sciadv.abo0309

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