Signal-reproducing method and apparatus utilizing light beam generated temperature distribution and magnetic domain wall displacement
US6345016B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 31, 1998 |
| Grant date | Feb 5, 2002 |
| Priority date | — |
| Expiry date | Aug 31, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B11/10593
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A signal reproducing method for reproducing information by domain wall displacement on a recording medium having recorded information comprises steps of projecting a light spot onto the recording medium to cause temperature distribution thereon, moving relatively the light spot and the recording medium, applying a reproducing magnetic field to the light spot area on the recording medium to prevent displacement of the domain wall from the rear portion of the moving light spot into the inside thereof, and detecting the domain wall displacement to reproduce the information. The temperature gradient may satisfy the relation below:|G1|>|G2|where G1 is the temperature gradient in the front portion in the moving direction, and G2 is the temperature gradient in the rear portion in the moving direction. The recording medium has a first magnetic layer enabling displacement of the domain wall, a third magnetic layer for memorizing information, and a second magnetic layer provided between the first magnetic layer and the third magnetic layer, and having a Curie temperature lower than the Curie temperature temperatures of the first magnetic layer and the third magnetic layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.