Magnetic Characteristics of Amorphous GdTbCoFe Thin Films

The temperature dependence of the coercive force (Hc) and the saturation magnetization (Ms) of GdTbCoFe quaternary amorphous films was studied. As the Co ratio in the transition metals (TM) increases, both the slope of Ms (T) and its maximum value increase. In the magneto-optical recording temperature range, Hc was small enough in all compositions to permit recording, but the magnetization values would vary with the Co concentration. Changes in the temperature dependence of Ms indicated that a small amount of Co would cause a transfer from Tc recording to Tcomp recording.