Heavy rare earth-Co substituted TbFe films for magneto-optical recording

The paper reports the Magnetic and magnetooptic data on sputter-deposited amorphous TbA-xR´xFeB-yCoy(R´=Dy, Ho or Er) films and the dynamic test to assure the adaptability for magneto-optical recording media. The substitution of Co for Fe atoms increases the Curie temperature Tfand coercive force, and therefore attains large Kerr rotation angle θk. The R´ substitution for Tb in this system suppresses the increase in Tfbut maintains the high θk. It is also important to save the rare Tb resource. A suitable read/write characteristics for high density recording with large θkis observed in the range of A=30 to 33 (B=100-A) and y=5 to 25.