The effect of spin-orbit coupling in a Josephson diode has not been elucidated due to its interplay with the complexity of Josephson devices. Here, we systematically control local electric fields in epitaxial Al-InAs Josephson junctions under in-plane magnetic fields and observe a polarity reversal of the Josephson diode. We interpret this polarity reversal as an effect of field-tunable spin-orbit coupling on nonreciprocal Josephson currents. A theoretical model, accounting for Rashba and Dresselhaus spin-orbit couplings in a planar Josephson junction containing many transverse subbands, aligns with the observed polarity reversal and its dependence on magnetic field. Our finding addresses spin-orbit control in a Josephson diode, enabling manipulation of Josephson harmonics.
@article{arxiv.2409.17820,
title = {Electric Control of Polarity in Spin-Orbit Josephson Diode},
author = {Junghyun Shin and Jae-Ho Han and Anjali Rathore and Joon Sue Lee and Seung-Bo Shim and Jinwoong Cha and Sunghun Park and Junho Suh},
journal= {arXiv preprint arXiv:2409.17820},
year = {2026}
}