Abstract
The origin of perpendicular magnetic anisotropy has been investigated in a thick Tb-Fe amorphous alloy plate prepared by dc high-rate sputtering. In the as-prepared samples with and without a Cu substrate, no distinct difference in perpendicular magnetic anisotropy was confirmed. After annealing, the perpendicular magnetic anisotropy in the sample with a Cu substrate was maintained, whereas that disappeared in the sample without a Cu substrate. Inducing thermal strains with an epoxy resin, the perpendicular magnetic anisotropy was restored. Therefore, it is concluded that the strong strains induced by the difference between the thermal expansion of the Tb-Fe amorphous alloy plate and the Cu substrate dominate to the origin of perpendicular magnetic anisotropy.
