Magneto-optical Kerr Eect Study of Magnetic Anisotropy in Soft Ferromagnets

The continued progress of modern information technology relies on understanding the influence of magnetic anisotropy on magnetic thin films. In this work, two sources of magnetic anisotropy are examined in two different soft ferromagnets: a uniaxial anisotropy induced during the fabrication of Ni80Fe20 and exchange anisotropy, or exchange bias, which occurs at the interface of Ni77Fe14Cu5Mo4/Fe50Mn50 bilayer. A home-built Magneto-optical Kerr effect magnetometer is used to measure the magnetic response of the soft ferromagnetic films and details of its construction are also discussed. A simple model of uniaxial anisotropy is described, then applied, to the uniaxial NiFe film and deviations from the model are critically analyzed. The exchange bias and coercive fields of NiFeCuMo/FeMn are reported for the first time and studied as a function of buffer layer material. The influence of the different buffer layer materials on the magnetization response of the bilayer is explained from a structural standpoint