Magnetic anisotropy in ferromagnetic Josephson junctions

Magnetotransport measurements were done on Nb/Al2O3/Cu/Ni/Nb superconductor-insulator-ferromagnet-superconductor Josephson tunnel junctions. Depending on ferromagnetic Ni interlayer thickness and geometry, the standard (1d) magnetic field dependence of critical current deviates from the textbook model for Josephson junctions. The results are qualitatively explained by a short Josephson junction model based on anisotropy and 2d remanent magnetization. (C) 2008 American Institute of Physics.