Thermally-assisted recording (TAR) disk drive with patterned multilevel media and laser with power modulation
US8081542B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 9, 2010 |
| Grant date | Dec 20, 2011 |
| Priority date | — |
| Expiry date | Nov 9, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/0021
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A thermally-assisted recording (TAR) patterned-media magnetic recording disk drive has a perpendicular patterned-media disk with multilevel data islands and a laser capable of supplying multiple levels of output power to a near-field transducer (NFT). If there are only two cells in each island, each island is formed of an upper cell of magnetic material with a coercivity HC1 and a Curie temperature TC1, a lower cell of magnetic material with a coercivity HC2 and a Curie temperature TC2 greater than TC1, and a nonmagnetic spacer layer between the two cells. Each cell is formed of high-anisotropy material so as to have an anisotropy field greater than the magnetic write field. The TAR laser is capable of supplying at least two levels of output power to the NFT to allow the islands to be heated to two distinct temperatures so that the two cells in an island can be written so as to have either the same or opposite magnetizations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.