Domain structures in soft-ferromagnetic thin-film objects (invited)

A self-consistent domain theory, based on micromagnetic principles, is unfolded for two-dimensional solenoidal M distributions present in ideally soft-magnetic plane-parallel thin-film objects at zero external field and in the absence of conduction currents. Two types of domain configurations are distinguished: the basic structures in simply connected regions and the parallel configurations in special types of multiply connected regions—the parallel regions. A decomposition of the objects’s area into disjunct subregions, either simply connected or of the parallel type, whose union completely covers the object, is put forward. A procedure for constructing all feasible parallel regions is presented. In each region, the appropriate solenoidal M distribution is specified with which M is taken parallel to the subregion’s boundary. Thus, all the domain structures possible in thin-film objects with arbitrary lateral shapes can be constructed. Experimental examples are provided.