Optimized Field Pulse for Quasi-1-D Magnetic Domain Wall Motion

In this paper, we analytically investigated the field-driven domain wall (DW) propagation along magnetic nanowires in the framework of the Landau-Lifshitz-Gilbert (LLG) equation. We proposed a new strategy to speed up DW motion in a uniaxial anisotropy nanowire by using an optimized space-dependent field pulse synchronized with the DW motion. Depending on the small damping parameter, the DW velocity can be increased by two orders of magnitude compared to the standard case of a static uniform field. Moreover, under the optimized field pulse, the change in total magnetic energy in nanowires is proportional to the DW velocity, implying that rapid energy release is essential for fast DW propagation. Besides, for large damping, we also proposed an optimized spatio-temporal pulse which can lead to the DW pinning with a fast angular rotation around the wire axis.