| 摘要 |
PURPOSE:To attain the overwriting of a magneto-optical recording by impressing a prescribed external magnetic field through the use of a magneto-optical recording medium consisting of two layer films satisfying a relation in which coercive forces and temperatures are specified and executing recording by means of laser irradiation. CONSTITUTION:A reading layer 9 consisting of a vertical magnetization film, and a writing layer 10 consisting of a ferromagnetic material being the perpendicular magnetization film are laminated on a substrate 7 through a dielectric layer 8. It is assumed that a room temperature is Tr, the coercive forces in the temperatures of the reading layer 9 and the writing layer 10 are HcR and HcW, the Curie temperatures of the reading layer 9 and the writing layer 10 are TcR and TcW, and the compensation temperature of the writing layer 10 is Tcomp-W, the relation of an inequality I is set to be satisfied. When the external magnetic field Hext. is impressed on the recording medium so as to satisfy an inequality II and a temperature where the magnetic field Hext. and the coercive force HcW become equal on a side higher than the temperature Tcomp-W is set to TB, a recording film is temperature- raised by laser irradiation so that an inequality III is satisfied, and then it is cooled. Next, the film is temperature-raised until it comes to a temperature where an inequality IV is satisfied, and it is cooled. Thus, the optical magnetic recording can be overwritten. |
