Enhanced critical current in YBa 2 Cu 3 O 7−δ thin films through pinning by ferromagnetic YFeO 3 nanoparticles

Nanoscale ferromagnetic inclusions of YFeO 3 have been incorporated into pulsed laser deposited YBa 2 Cu 3 O 7 − δ (YBCO) thin films. The poisoning of the YBCO through the addition of the magnetic material is minor, with 1 mol% doping resulting in an unsuppressed superconducting transition temperature of 90 K. The critical current density of the magnetically doped films is enhanced both in field and at self-field, and values of 3.0 MA cm − 2 have been achieved at 77 K, self-field in films 1 µm thick, compared to 1.5 MA cm − 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.