Anisotropic atomic structure of TbFe and TbCo amorphous alloys

The uniaxial anisotropy of Tb19Co81 and Tb19Fe81 amorphous alloy films was investigated by using X-ray diffraction analysis and measuring the magnetic anisotropy constants, Ku, on annealing at 200°C. It was revealed that, in the TbFe film investigated, the anisotropic structure was more extensively relaxed at an early stage of annealing than in the TbCo film. During this relaxation process, near-neighboor correlations changed mainly around TbTb pairs in the TbFe film, whereas they changed mainly around CoCo pairs in the TbCo film. The magnetic anisotropy decreased more rapidly in the TbFe film than in the TbCo film, reflecting this difference in the structural relaxation process. © 1992.