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  • Letter
  • Open Access

Multiband superconductors under magnetic fields: Fractional vortices and Ising superconductivity

Haijiao Ji and Noah F. Q. Yuan*

  • *Contact author: fyuanaa@connect.ust.hk
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Phys. Rev. Research 7, L012010 – Published 15 January, 2025

DOI: https://doi.org/10.1103/PhysRevResearch.7.L012010

Abstract

Inspired by the recent experiments in monolayer iron-based superconductors, we theoretically investigate the properties of a two-dimensional multiband superconductor under magnetic fields, focusing on two aspects. First, for vortex bound states under out-of-plane magnetic fields, the spatial anisotropy and positions of electron density peaks are associated with interband couplings. Second, under in-plane magnetic fields, even with inversion symmetry, a Ising-type spin-orbit coupling is allowed, leading to an enhanced in-plane upper critical field. Applications to other two-dimensional multiband superconductors are also discussed.

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Phys. Rev. Research 7, L012010– Published 15 January, 2025
  • Received 6 August 2024
  • Accepted 23 December 2024
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