Large artificial ferromagnetic dot arrays for the critical current enhancement in superconducting YBa2Cu3O7-δthin films

Authors

Mustafa Al-Qurainy, University of WollongongFollow
Alison L. Jones, University of WollongongFollow
S Rubanov
Sergey Fedoseev, University of WollongongFollow
I Rudnev
Alaa Hamed Hamood, University of WollongongFollow
Alexey Pan, University of WollongongFollow

RIS ID

145681

Publication Details

Al-Qurainy, M., Jones, A., Rubanov, S., Fedoseev, S., Rudnev, I., Hamood, A. & Pan, A. (2020). Large artificial ferromagnetic dot arrays for the critical current enhancement in superconducting YBa2Cu3O7-δthin films. Superconductor Science and Technology, 33 (10),

Abstract

© 2020 IOP Publishing Ltd. In order to enhance and/or control critical current density (J c) in superconducting YBa2Cu3O7-δ (YBCO) thin films, different arrays of 3 µm large ferromagnetic (iron) dots with differing configurations and shapes have been deposited on top of high-quality YBCO thin films post-buffered with a layer of CeO2. Some tremendous J c enhancement of up to nearly 100% have been obtained at high temperatures and low fields. However, the J c performance is strongly dependent on the array configurations, shape and amount of ferromagnetic iron involved. We show that it is possible to enhance J c at high or low magnetic field ranges. The results are clearly different to similar non magnetic array structures used to previously manipulate J c in YBCO films, which proves the magnetic origin of the changes in J c we observed. The enhancement is likely due to the flux localization and magnetic pinning effects, rather than magnetic shielding alone, which is effective at relatively low fields only. The results also suggest that the observed J c changes depend on rather minor variations in initial pinning and corresponding J c levels of the films. At the same time a common trend for all of the various investigated magnetic arrays could not be established due to explained factors.