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arXiv · 2409.20336

Orbital-FFLO State and Josephson Vortex Lattice Melting in Layered Ising Superconductors

Hongyi Yan·Haiwen Liu·Yi Liu·Ding Zhang·X. C. Xie
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Abstract

This study explores the impact of in-plane magnetic fields on the superconducting state in layered Ising superconductors, resulting in the emergence of the orbital Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state coupled with Josephson vortices. Recent experiments have revealed an unexpected first-order phase transition in these superconductors under strong in-plane magnetic fields. Our theoretical analysis demonstrates that this phase transition is primarily driven by the formation and subsequent melting of a Josephson vortex lattice within the superconducting layers. As the magnetic field increases, the vortex lattice undergoes a transition from a solid to a liquid state, triggering the observed first-order phase transition. We calculate both the melting line and the in-plane critical field in the phase diagram, showing strong agreement with experimental results.

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Hongyi Yan, Haiwen Liu, Yi Liu, Ding Zhang, X. C. Xie. 2024-09-30. Orbital-FFLO State and Josephson Vortex Lattice Melting in Layered Ising Superconductors. https://arxiv.org/abs/2409.20336

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