Simulations of Field Driven Domain Wall Interactions in Ferromagnetic Nanowires

The interaction of domain walls in a single ferromagnetic nanowire has been observed with micromagnetic simulation. Domain walls separating domains of opposite magnetization move towards each other when an external field is applied along the long axis of the wire resulting in a collision. The final magnetic state of the wire after the collision will contain either zero (domain wall annihilation) or two (domain wall conservation) domain walls. Here we explore the behavior that determines the final state, showing that it depends on the initial domain wall configuration, the speed the domain walls are moving with before the collision, and the dimensions of the nanowire. A model is also presented which helps to determine the repulsive force the conserved domain walls exert on each other.