Dynamic dependence to domain wall propagation through artificial spin   ice
  Domain wall propagation dynamics have been studied in nanostructured artificial kagome spin ice structures. A stripline circuit has been used to provide localised pulsed magnetic fields within the artificial spin ice structure. This provides control of the system through electrically assisted domain wall nucleation events. Synchronisation of the pulsed fields with additional global magnetic fields and the use of a focussed magneto-optical Kerr effect magnetometer allows our experiments to probe the domain wall transit through an extended ASI structure. We find that the propagation distance depends on the driving field revealing field driven properties of domain walls below their intrinsic nucleation field. 
D.M. Burn, M. Chadha, and W.R. Branford
cond-mat.mes-hall