Domain Nucleation in Magnetic Thin Films by Localized Fields Produced by Thin Stripline

Abstract

The nucleation of reversed domains has been studied by means of the Kerr magnetooptical apparatus for a continuous planar film subjected to an easy direction local dc field produced by a microstripline and a hard direction homogeneous dc field. From the observed domain patterns, the mode of the domain nucleation is categorized into the following two types, depending on the intensity of the hard direction field. For the small hard direction fields, the domain nucleation takes place uniformly over all the area covered by the stripline. For the large hard direction fields, the nucleation takes place nonuniformly in the area under the stripline so that the island-shaped reversed domains appear at almost equal spacings along the stripline. These interesting phenomena associated with the domain nucleation are understood clearly on the basis of the one-dimensional model.