Magnetic Properties of Amorphous Rare Earth-Transition Metal Alloy Films

Changes in the average magnetic moment in sputtered Fe-Co film accompanying substitution of Co for Fe and the addition of Bi are reported. Average magnetic moments μTM were calculated from measured values of the saturation magnetization at 4.2 K. The dependences of μTM on the Co concentration y in Gd-Fe-Co-Bi, Gd-Fe-Co and Tb-Fe-Co films are described. Magnetic moments of individual atoms in the systems are estimated. For both Tb-Fe-Co and Gd-Fe-Co films with small Co contents (0 ≤ y ≤ 0.3), the μTM was essentially constant at 1.9 μB.