Magnetization reversal in a soft magnetic nanowire

The analysis of ferromagnetic nanowires is a new and vivid field of research. Micromagnetic simulations based on the Gauss-Seidel Projection Method (GSPM) is very efficient for simulating the magnetic behavior and is being used to gain an insight into the dynamics of the reversal process of both thin and thick wires. Two different types of reversal modes occur, depending on the wire thickness. While in thin wires a simple domain wall called transverse wall nucleates and propagates along the wire axis, the reversal of thick wires is achieved via a localized curling mode. The latter mode involves the injection and propagation of a micromagnetic singularity (Bloch point). Further point singularities may be generated and annihilated periodically during the reversal process. This results in the temporary formation of micromagnetic drops, i.e., isolated, non-reversed regions. This surprising feature in dynamic micromagnetism is due to different mobilities of domain wall and Bloch point