| 摘要 |
PURPOSE:To increase Kerr rotation angle thetaK in an amorphous alloy magnetic material and thereby to improve optical reproduction characteristics, by employing a material consisting essentially of Gd-Tb-Fe-Co-M which has an easy magnetization axis perpendicular to the film plane. CONSTITUTION:An amorphous magnetooptical layer is employed which is made of a material consisting essentially of Gd-Tb-Fe-Co-M (wherein M is at least one element selected from among Sn, Ni, Cr, Bi and Cu) and which has an easy magnetization axis perpendicular to the film plane. This magnetic layer needs to have perpendicular magnetic anisotropy and preferably has high coercive force. When the composition of the magnetic material constituting the magnetic layer is expressed by {(GdxTb1-x)y(Fe1-zCoz)1-y}1-aMa, it is preferable to meet the conditions of 0<x<1, 0.1<=y<=0.4, 0.01<=z<=0.5, and 0.001<=a<=0.1. The amorphous magnetooptical layer is formed on an appropriate carrier so that the film thickness is about 0.01-1mm by an appropriate method such as vacuum deposition, sputtering, or ion plating.
|
