DOMAIN STRUCTURE AND INFLUENCE OF GROWTH DEFECTS IN SINGLE CRYSTALS OF YTTRIUM IRON GARNET

Thin slices of single crystals of yttrium iron garnet were prepared free from mechanical polishing strains by chemical polishing in hot phosphoric acid. The magnetic domain structure was investigated using transmitted polarized light. 180°Bloch walls with a periodic structure of right- and left-hand sections were found to be tilted at the Bloch lines separating the sections. In specimens containing growth defects, for example dislocations or growth striations, the domain structure was markedly changed, in the latter case by the rotation of the magnetization out of the easy direction in the plane of the slice. The significance of the interaction with respect to domain-wall motion experiments using picture frame specimens is discussed. © 1968 The American Institute of Physics.