发明名称 |
Perpendicular magnetic recording medium with exchange-spring structure having multiple exchange-spring layers and recording system for the medium |
摘要 |
A perpendicular magnetic recording system uses an exchange-spring type of perpendicular magnetic recording medium. The medium has a recording layer (RL) that includes a lower media layer (ML) and a multilayer exchange-spring layer (ESL) above the ML. The high anisotropy field (high-Hk) lower ML and the multilayer ESL are exchange-coupled across a coupling layer. The multilayer ESL has at least two ESLs separated by a coupling layer, with each of the ESLs having an Hk substantially less than the Hk of the ML. The exchange-spring structure with the multilayer ESL takes advantage of the fact that the write field magnitude and write field gradient vary as a function of distance from the write pole. The thicknesses and Hk values of each of the ESLs can be independently varied to optimize the overall recording performance of the medium.
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申请公布号 |
US7572526(B2) |
申请公布日期 |
2009.08.11 |
申请号 |
US20070676299 |
申请日期 |
2007.02.18 |
申请人 |
HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V. |
发明人 |
BERGER ANDREAS KLAUS;FULLERTON ERIC E.;LENGSFIELD, III BYRON HASSBERG |
分类号 |
G11B5/66;G11B5/667;G11B5/673;G11B5/716 |
主分类号 |
G11B5/66 |
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