Magneto-optical recording medium having multiple magnetic layers
US5903526A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 17, 1997 |
| Grant date | May 11, 1999 |
| Priority date | — |
| Expiry date | Sep 17, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B11/10521
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Magneto-optic recording medium has at least a 1st magnetic layer for recording information signals, a 2nd magnetic layer formed on the 1st magnetic layer and a 3rd magnetic layer formed on the 2nd magnetic layer. The 1st and 3rd magnetic layers are made of a first amorphous material of rare earth and 3d transition metal having perpendicular magnetic anisotropy in a direction perpendicular to a surface thereof, respectively. The 2nd magnetic layer is interposed between the 1st and 2nd magnetic layers as an intermediate layer. The 2nd magnetic layer is made of a second amorphous material of rare earth metal and 3d transition metal with rare earth metal rich (RE-rich) having a smaller exchange energy between the rare earth metal and a 3d transition metal than that of Gd--Fe or Gd--Fe--Co and having magnetic anisotropy in a direction parallel to a surface of the 2nd magnetic layer, wherein the 1st and the 3rd magnetic layers are magnetically coupled through the 2nd magnetic layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.