Nonreciprocal Josephson current through a conical magnet

Lina Johnsen Kamra; Liang Fu

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arXiv · 2409.00223

Nonreciprocal Josephson current through a conical magnet

Lina Johnsen Kamra·Liang Fu

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Abstract

Superconductors can form ideal diodes carrying nondissipative supercurrents in the forward direction and dissipative currents in the backward direction. The Josephson diode has proven to be a promising design where the junction between the two superconductors comprises the weakest link and thus provides the dominant mechanism. We here propose a Josephson diode based on a single magnetic material with a conical spin structure. The helical spin rotation produces Rashba-like band splitting inversely proportional to the rotation period. Together with the Zeeman splitting caused by the time-reversal symmetry breaking of the noncoplanar spin texture, this results in a large diode efficiency close to the $0-\pi$ transition of the magnetic Josephson junction.

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Lina Johnsen Kamra, Liang Fu. 2024-08-30. Nonreciprocal Josephson current through a conical magnet. https://arxiv.org/abs/2409.00223

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