Domain and Domain Wall Structures of Layered Magnetic Films

The domain and domain wall structures of double-layered Co-Nb-Ti magnetic films, with SiO2 films of varying thicknesses interposed between the magnetic layers were studied. It was found that domain and domain wall structures changed as the thickness of the SiO2 film increased, which can be explained by the change in magnetic coupling between the upper and lower magnetic layers. The coupling between the magnetic layers varied largely within the SiO2 thickness range much less than the wall thickness, which differs from the reported results for Permalloy films.