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arXiv · 2508.12056

Voltage-tunable field-free Josephson diode

Sjoerd Telkamp·Junting Zhao·Saulius Vaitiekėnas
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Abstract

We report a gate-tunable Josephson diode effect in hybrid nanowire junctions consisting of a spin-orbit-coupled semiconductor core coated with epitaxial ferromagnetic insulator and superconductor shells. The wires display a hysteretic superconducting window as a function of axial magnetic field. In the superconducting regime, the devices exhibit nonreciprocal supercurrent transport, with the diode efficiency showing a strong dependence on back-gate voltage. The effect persists in a remanent magnetization state following a controlled demagnetization procedure, establishing zero-field operation. These findings demonstrate a voltage-controlled Josephson diode in a single junction and suggest a route toward probing intrinsically broken inversion and time-reversal symmetries in hybrid materials.

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Sjoerd Telkamp, Junting Zhao, Saulius Vaitiekėnas. 2025-08-16. Voltage-tunable field-free Josephson diode. https://arxiv.org/abs/2508.12056

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