Magnetic after-effect in sputter deposited TbxFe1−x (x×0.17∼0.24) films is studied. The after-effect is directly observed using polar Kerr magneto-optic effect as a slow propagation of domain walls. The velocity of the domain growth (10−4∼10−1 cm/s) changes exponentially with the applied field. The viscosity coefficient Sv≡dM/d ln t·χ−1 (χ: irreversible susceptibility), which was used in describing Jordan type after-effect, is applied to characterize the after-effect. The value of Sv (22∼110 Oe) is inversely proportional to the saturation magnetization at room temperature and decreases with rising temperature. The origin of the slow wall motion is inferred to be the random anisotropy of Tb ion rather than the oxidation of the film surface.
ASJC Scopus subject areas
- Physics and Astronomy(all)