Observation of Magnetic Domain Structures of Magnetic Thin Films by the Lorentz Electron Microscopy

The microstructure change in thin NiFe/Cu/NiFe films during the magnetization process was observed by the Lorentz electron microscopy. Two types of films were prepared: (1) one NiFe layer with anisotropy and the other layer without, and (2) both NiFe layers have anisotropy normal each other. The domain wall migration and magnetization rotation processes in each of NiFe layers could be observed separately. The presence of magnetic anisotropy in the magnetic layer effectively controls the behavior of magnetic domains. The interaction between the two NiFe layers of the film could be observed not so strong in the present experiment.