In this study, we investigate the magnetization behavior of coaxial nanowires fabricated
through the sol-gel electrospinning method. Our analysis uncovers a significant reduction in coercivity for CoFe2O4 nanowires when BaTiO3 is used as the shell material, effectively transforming
them from hard to soft magnetic. This intriguing behavior is attributed to the magnetization reversal
effect at the interface between ferromagnetic and paramagnetic regions, and it is also observed in
NiFe2O4 and Fe2O3 nanowires. Surprisingly, introducing a GdBa2Cu3O7 shell induces a similar effect.
Additionally, we employ magnetic impedance measurements on the coaxial nanowires, unveiling
their potential for magnetic field sensing applications
