Perpendicular magnetic recording head laminated with AFM-FM phase change material
US8004794B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 21, 2007 |
| Grant date | Aug 23, 2011 |
| Priority date | — |
| Expiry date | May 15, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49044
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A PMR writer is disclosed that minimizes pole erasure during non-writing and maximize write field during writing through an AFM-FM phase change material that is in an AFM state during non-writing and switches to a FM state by heating during writing. The main pole layer including the write pole may be comprised of a laminated structure having a plurality of “n” ferromagnetic layers and “n−1” AFM-FM phase change material layers arranged in an alternating manner. The AFM-FM phase change material is preferably a FeRh or FeRhX alloy (X=Pt, Pd, or Ir) having a Rh content >35 atomic %. AFM-FM phase change material may also be used as a flux gate to prevent yoke flux from leaking into the write pole tip. Heating for the AFM to FM transition is provided by write coils and/or a coil located near the AFM-FM phase change material to enable faster transition times.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.