Magnetic Domain Structures in CoCr Films Studied by Lorentz Microscopy

Magnetization distribution and behavior of magnetization in CoCr sputtered films of various thickness are studied by high-resolution Lorentz microscopy. The perpendicular component of magnetization increases with increasing film thickness, corresponding to the increase in the Q-value. The dominant mechanism of magnetization reversal changes from the domain wall displacement mode in the 200 A thick film to the rotational mode in the 1000 A thick film. In the 600 A thick film, elongated domains with a kind of cross-tie walls are formed perpendicular to an AC demagnetizing field in the film plane.