J. Phys. IV France 08 (1998) Pr2-307-Pr2-310
Characterization of microstructural defects from temperature dependence of domain wall coercive fieldJ. Kadlecová1, K. Metlov1, Tomás1 and G. Vértesy2
1 Institute of Physics, ASCR Na Slovance 2, 180 40 Prague 8, Czech Republic
2 Research Institute for Materials Science, HAS, P.O. Box 49, 1525 Budapest, Hungary
The steep temperature dependence of the domain wall coercive field. HCW(T), of highly anisotropic rare earth magnetic garnet films, recently described as a piece-wise exponential curve, was analysed. The quantitative analysis revealed the HCW(T) shape to be caused by the exponential temperature dependence of the anisotropy field, modified by functions describing the efficiency of the wall-defects interaction, at least for two different sets of defects. Characteristic periods of the two sets of defects were found and the defects were identified in one case with point defects caused by local fluctuation of the anisotropy constant at sites of individual rare earth ions in the crystal lattice and in the other case with fluctuation of local stresses due to local fluctuation of the material composition.
© EDP Sciences 1998