| 摘要 |
PURPOSE:To obtain a magneto-optical recording medium which has a large degree of freedom in designing compsn. and allows overwriting by forming a transition metal-heavy rare earth alloy which is rich in heavy rare earths and satisfy specific conditions as a 1st layer and 2nd layer. CONSTITUTION:The magneto-optical recording medium which has perpendicularly magnetized films having at least two-layered structure consisting of the 1st layer, the 2nd layer and substrate and allows the over-writing is constituted of the following compsn.: The 1st and 2nd layers are constituted of the transition metal-heavy rare earth alloy which is rich in the heavy rare earths, has a compensation temp. between room temp. and Curie temp., and satisfies the equations I-V. The over-writing is enabled by this compsn. if the continuous magnetic field changing continuously from the initial auxiliary magnetic field to recording magnetic field is used. The magneto-optical recording medium which has the large degree of freedom in designing the compsn. and allows the over-writing is thereby obtd. In the equations, Hc2: the coercive force of the 2nd layer, MS1: the saturation magnetic moment of the 1st layer, MS2: the saturation magnetic moment of the 2nd layer, t1: the film thickness of the 1st layer, t2: the film thickness of the 2nd layer, 6W: boundary magnetic wall energy, Hini: initial auxiliary magnetic field, Hb: recording magnetic field. |
