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  • Letter
  • Open Access

Spin-split Andreev bound states and diode effect in an Ising superconductor Josephson junction

Sourabh Patil1, Gaomin Tang2,*, and Wolfgang Belzig1,†

  • 1Fachbereich Physik, Universität Konstanz, D-78457 Konstanz, Germany
  • 2Graduate School of China Academy of Engineering Physics, Beijing 100193, China

  • *Contact author: gmtang@gscaep.ac.cn
  • †Contact author: wolfgang.belzig@uni-konstanz.de
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Phys. Rev. B 111, L060502 – Published 12 February, 2025

DOI: https://doi.org/10.1103/PhysRevB.111.L060502

Abstract

The transition-metal dichalcogenides featuring Ising spin-orbit coupling in so-called Ising superconductors offer a unique system to study the interplay of singlet and triplet superconductivity. The presence of high critical fields, spectral properties such as the mirage gap, and field-tunable charge and spin currents in Ising superconductor Josephson junctions are some of the important features. In this Letter, we study an Ising superconductor Josephson junction with a transparent interface and show that Andreev bound states are spin split due to a relative misorientation of in-plane fields in the superconducting contacts. Correspondingly, supercurrent-phase relations display a strongly nonsinusoidal behavior. Introducing additional spin-polarized channels with low transmission results in a nonreciprocal current-phase relation with a diode effect that can be tuned by the in-plane exchange fields. The diode efficiency reaches high values of the order of 40% and is not sensitive to disorder in the junction. Such structures can be realized in van der Waals heterostructures of two-dimensional superconductors and magnets.

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Phys. Rev. B 111, L060502– Published 12 February, 2025
  • Received 6 November 2024
  • Revised 22 January 2025
  • Accepted 27 January 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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