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Abstract-Pulsed-current controlled wall motion in 20 m wide 200 m long 160 nm thick patterned Permalloy strips was studied using magnetic force microscopy. By sequential imaging, the displacement of Bloch walls as far as 200 m along the strip was observed. The direction of motion was in the same direction as the carrier velocity, which reversed with current polarity. The displacement per pulse was dependent upon the sample thickness and current density, which suggests that the mechanism is a combination of s-d exchange and hydromagnetic domain drag forces.

The magnetization distributions of an array of small NiFe elements were studied using Lorentz transmission electron microscopy (LTEM) and magnetic force microscopy (MFM). The dependence of the domain configurations at zero field as a function of the aspect ratio was observed using MFM, and confirms the earlier observations using LTEM. Comparison of the images of similar islands using both techniques elucidate the complementarity between the LTEM and MFM measurements which individually show different facets of the magnetization distributions on soft magnetic thin films.