Corner clusters in thin soft magnetic layers: The corner cluster—a system of walls

Abstract

The domain-wall cluster is a new concept revealing a large number of features about the domain structure and its conversions in thin soft magnetic layers, as used in field-access bubble devices and in integrated tape recorder heads. A wall cluster is a collection of domain walls having one intersection line, the so-called cluster knot, in common. This paper is confined to the relations in the mutual domain-wall positions in the corner clusters, characterized by a cluster knot that coincides with a corner of the geometry. A one-to-one relationship between the domain-wall positions and the magnetization distribution near the corner exist in a special class of corner clusters, the so-called completely uniform corner clusters. It is shown under which conditions this type of cluster might or have to occur. The other class of corner clusters contains rotation segments, defined as sectors in which the magnetization rotates circularly around the cluster knot. The circulation sense of the magnetization in the rotation segments of a specific cluster is the same for all segments. The magnetization distribution possible in this class of clusters systematically come up for review. Consequently, the paper offers a framework for the interpretation of the observations obtained in the Bitter, TEM and Kerr techniques.