A1 Refereed original research article in a scientific journal
A Structural Optimization of Ferrite/YBCO Bilayers
Authors: Mika Malmivirta, Jaakko Jyrinki, Hannu Huhtinen, Alexey V. Pan, Sergey Rubanov, R. Jha, V. P. S. Awana, Petriina Paturi
Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Publication year: 2017
Journal: IEEE Transactions on Applied Superconductivity
Journal name in source: IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY
Journal acronym: IEEE T APPL SUPERCON
Article number: ARTN 8000705
Volume: 27
Issue: 4
Number of pages: 5
ISSN: 1051-8223
eISSN: 1558-2515
DOI: https://doi.org/10.1109/TASC.2016.2643445
Abstract
Magnetic particles can be used to take advantage of both defect and magnetic pinning in high-temperature superconductors. We combined layers of ferrite+cerium oxide with YBCO to see their effect both on the structure of the YBCO and on flux pinning. The deposition temperature of the ferrite greatly affects its structure and also the saturation magnetization. Combined with YBCO, the magnetic layer distorts the structure of YBCO, although, for example, the critical temperature remains rather unchanged. According to the structural results achieved here, the magnetic pinning layer is best positioned on the top of YBCO. This way, an improvement in J(c)(B) is seen in all the field range, and also, a clear improvement of the accommodation field was measured. However, it does not play a huge role whether the ferrite is CoFe2O4, NiFe2O4, or ZnFe2O4, all mixed with CeO2.
Magnetic particles can be used to take advantage of both defect and magnetic pinning in high-temperature superconductors. We combined layers of ferrite+cerium oxide with YBCO to see their effect both on the structure of the YBCO and on flux pinning. The deposition temperature of the ferrite greatly affects its structure and also the saturation magnetization. Combined with YBCO, the magnetic layer distorts the structure of YBCO, although, for example, the critical temperature remains rather unchanged. According to the structural results achieved here, the magnetic pinning layer is best positioned on the top of YBCO. This way, an improvement in J(c)(B) is seen in all the field range, and also, a clear improvement of the accommodation field was measured. However, it does not play a huge role whether the ferrite is CoFe2O4, NiFe2O4, or ZnFe2O4, all mixed with CeO2.