Controlled reversal of coupled Neel walls in flux-closure magnetic trilayer elements

摘要

We report the detailed field-induced transformation of coupled Neel walls in micron-sized trilayer elliptical elements for novel domain-wall-based device applications. Using in situ Lorentz transmission electron microscopy and micromagnetic simulation, we demonstrate that the magnetostatically coupled composite wall structure can be switched controllably without affecting the overall flux-closure domain configuration via separate translation of vortex cores in the two magnetic layers. The top and bottom Neel walls either trap or expel each other depending on the relative orientation of their magnetization directions, leading to the interesting domain switching behavior observed during magnetization reversal.