The Type-II/Type-I Crossover in Dirty Ferromagnetic Superconductors.

In this work, we investigate the intertype (IT) domain in strongly disordered ferromagnetic superconductors with a Curie temperature lower than the superconducting critical temperature. In such unique materials, the coexistence of superconductivity and ferromagnetism allows for the exploration of both unconventional superconductivity and the interplay between magnetism and superconductivity. The study utilizes an extended Ginzburg-Landau model for the dirty limit to calculate the boundaries of the IT domain, which is characterized by a complex vortex-vortex interaction and exotic vortex configurations. The analysis reveals that the IT domain in dirty ferromagnetic superconductors is not qualitatively different from that in the clean case and remains similarly large, suggesting that disorder does not hinder the exploration of the rich variety of IT superconductivity in ferromagnetic superconductors. This work expands our understanding of the interplay between superconductivity and magnetism in complex materials and could guide future experimental studies.