Domain Wall Velocities in Thin Magnetic Films

Wall mobility measurements employing short pulse drive fields show that in films with thicknesses up to 2000 Å the wall velocity is determined by spin relaxation effects rather than by eddy current damping. Further, it seems probable (a) that for high wall velocities the viscous flow approximation is no longer valid, (b) that Bloch lines are responsible for the low mobility of cross-tie walls and (c) that the energy dissipation that is related to a near moving domain walls is larger in films with higher H
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