Enhanced critical current in YBa₂Cu₃O _7-δ thin films through pinning by ferromagnetic YFeO ₃ nanoparticles

Nanoscale ferromagnetic inclusions of YFeO₃ have been incorporated into pulsed laser deposited YBa₂Cu₃O _{7 - δ} (YBCO) thin films. The poisoning of the YBCO through the addition of the magnetic material is minor, with 1mol% doping resulting in an unsuppressed superconducting transition temperature of 90K. The critical current density of the magnetically doped films is enhanced both in field and at self-field, and values of 3.0MAcm^-2 have been achieved at 77K, self-field in films 1νm thick, compared to 1.5MAcm^-2 in an undoped film prepared by the same process. Such an enhancement in critical current at such low dopant levels is suggestive of an additional contribution to the flux pinning from the magnetic constituent.