| 摘要 |
PURPOSE:To enable optically modulated overwriting in magnetic layers and to smoothen recording in the magnetic layers because magnetic coupling of the magnetic layers does not occur at room temp. but occurs at high temp. at the time of recording. CONSTITUTION:A magnetic layer 3, a magnetic layer 4 and a magnetic layer 5 each mode of a rare earth metal-transition metal alloy are successively formed. The magnetic layer 3 exhibits perpendicular magnetic anisotropy in the temp. range from room temp. to the Curie point. The magnetic layer 4 has a higher Curie point than the magnetic layer 3, has nearly zero coercive force at room temp. and exhibits intrasurface magnetic anisotropy at room temp. and perpendicular magnetic anisotropy at a prescribed temp. or above. The magnetic layer 5 exhibits perpendicular magnetic anisotropy in the temp. range from room temp. to the Curie point and has a higher Curie point than the magnetic layer 3, lower coercive force at room temp. than the magnetic layer 3 and a higher compensation point than the magnetic layer 4. |
