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arXiv · 2410.07337

Voltage-tunable spin supercurrent nonreciprocity reaching 100% efficiency

Chi Sun·Johanne Bratland Tjernshaugen·Jacob Linder
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Abstract

The superconducting version of a diode effect has been the subject of extensive research in the past few years. So far, the focus has almost exclusively been on charge transport, but a natural question is whether it is possible to obtain nonreciprocal spin transport without dissipation. Here, we demonstrate that it is possible to generate electrically tunable nonreciprocal spin transport carried by a supercurrent using superconductor/ferromagnet multilayers. The nonreciprocal spin supercurrent reaches an ideal efficiency of 100%, meaning that the spin-polarization of the critical current is finite in one flow direction whereas it vanishes in the other direction. We explain the underlying physics generating this phenomenon. This result provides a way to integrate nonreciprocal supercurrents with spin-polarization, offering new functionality in quantum technologies based on Josephson junctions.

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Chi Sun, Johanne Bratland Tjernshaugen, Jacob Linder. 2025-08-05. Voltage-tunable spin supercurrent nonreciprocity reaching 100% efficiency. https://arxiv.org/abs/2410.07337

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