High resolution measurement and modelling of magnetic domain structures in epitaxial FePd (001) L10 films with perpendicular magnetization

Magnetic domain structures in two 50 nm thick chemically-ordered FePd (001) epitaxial films with different perpendicular anisotropies have been studied using Lorentz microscopy. Domain and domain wall structures vary significantly according to the magnitude of the anisotropy. For lower anisotropy films, a stripe domain structure with a period of ≈100 nm is formed in which there is a near-continuous variation in orientation of the magnetization vector. By contrast, in the film with higher anisotropy, a maze-like domain structure is supported. The magnetization within domains is perpendicular to the film plane and adjacent domains are separated by narrow walls, less than 20 nm wide. Micromagnetic modelling is generally in good quantitative agreement with experimental observations and provides additional information on the domain wall structure