Magnetic pinning in a superconducting film by a ferromagnetic layer with stripe domains

Journal Article · Fri Oct 31 04:00:00 EDT 2014 · Superconductor Science and Technology

DOI:https://doi.org/10.1088/0953-2048/27/12/125002· OSTI ID:1357029

Mancusi, D.; Di Giorgio, C.; Bobba, F.; Scarfato, A.; Cucolo, A. M.; Iavarone, M.; Moore, S. A.; Karapetrov, G.; Novosad, V.; Yefremenko, V.; Pace, S.; Polichetti, M.

A magnetic study of superconductor/ferromagnet bilayers was performed by hysteresis loops and temperature-dependent magnetization measurements. The superconductor/ferromagnet bilayers consist of a Nb film deposited on a Py film with weak perpendicular magnetic anisotropy. By comparing the temperature-dependent magnetization data obtained on samples with different ferromagnetic layer thickness, a decrease of the magnetic pinning with increasing thickness of the ferromagnetic layer has been found. This is confirmed by the reduction of the Nb film critical current density at low fields extracted by using the magnetic irreversibility of the hysteresis loops. As the ferromagnetic layer exhibits a magnetic structure with stripe domains, whose width increases for increasing thickness as observed by magnetic force microscopy (MFM) measurements, we relate the reduction of the superconducting critical current in samples with thicker ferromagnetic layers to a weaker interaction between the vortices guided by the underlying magnetic template.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: USDOE Office of Science - Office of Basic Energy Sciences - Materials Sciences and Engineering Division
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 1357029
• Journal Information: Superconductor Science and Technology, Journal Name: Superconductor Science and Technology Journal Issue: 12 Vol. 27; ISSN 0953-2048
• Publisher: IOP Publishing
• Country of Publication: United States
• Language: English