Domain-wall dynamics in nanowires and nanostrips

Abstract

In nanowires or nanostrips, the magnetic domain walls have structures that depend sensitively on the transverse sizes of these samples. These domain-wall structures govern the dynamics of the walls under an applied field, so that rather different wall velocities can result from small changes in the sample transverse dimensions. These phenomena are first presented and discussed using results of micromagnetic simulations. In order to understand them, a model - valid in the limit of vanishing transverse dimensions - is introduced. It is shown that, however, this model applies also to the more complex domain-wall structures that exist at larger transverse sizes, qualitatively but even quantitatively in some cases. A procedure for determining the effective parameters of this model is given. Comparison to available experimental results is performed whenever possible. © Springer-Verlag Berlin/Heidelberg 2006.