ANISOTROPY OF QUASI-STATIC MAGNETIZATION-REVERSAL PROCESSES IN (210)-ORIENTED IRON-GARNET FILMS

An experimental study is made of the effect of an in-plane field H-p o f various orientations on the domain structure and shape of the hyster esis loops of epitaxial iron garnet films with the (210) orientation. The characteristic of the magnetization reversal process (in fields so mewhat lower than the anisotropy field) is taken to be the critical fi elds H-p1, Hp(2,) and H-p3, for which the magnetization reversal proce sses is interrupted at distinct stages. A method is proposed for const ructing the phase diagram of the magnetic states of films, using measu rements of the critical fields H-p for different amplitudes of the mag netization reversal field H-z. Two directions in the plane of the film are determined with an accuracy of a fraction of a degree from the hy steresis loops, where in the corresponding held H-p the transition fro m a single-domain state to a multidomain state occurs as a second-orde r phase transition. The characteristic changes in the shape of the hys teresis loop are consistent with the features in the reorganization of the domain structure of the (210) film. The preferential orientations of the stripe domain structure of the samples are determined relative to the crystal axes as determined by x-ray methods. (C) 1997 American Institute of Physics.