Determination of the local variation of the magnetic properties of liquid-phase epitaxial iron garnet films

This paper supplements and assesses an optical measuring technique for the local determination of the cubic and uniaxial anisotropy fields K1/Ms and Ku/Ms in uniaxial magnetic films reported in a recent paper. Graphs for the quick evaluation of the Ku/Ms values are given. The accuracy of the method is assessed by comparison with FMR measurements. The origin of the nonuniformity in the domain pattern of a (111) LPE garnet film with the chemical composition Y2.5Gd0.5Fe4Ga1O12 grown on a GGG substrate is investigated by local optical measurements of the magnetic film parameters K1/Ms, Ku/Ms, compensation temperature, and magneto-optic Faraday rotation. It is correlated with local structural parameters of the substrate as stress birefringence from ellipsometric measurements and inhomogeneity of the lattice constant measured by x-ray topography.