Perpendicular magnetic recording medium
AssigneeFuji Electric Co., Ltd.
InventorSadayuki Watanabe
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Abstract
A perpendicular magnetic recording medium is disclosed that enables a high track density while maintaining good OW characteristics, SNR, and thermal stability. The medium includes a magnetic recording layer on a non-magnetic base, wherein the magnetic recording layer includes a first magnetic layer, a first exchange coupling control layer, a second magnetic layer, a third magnetic layer, and a fourth magnetic layer, in that order. It is preferable that when the perpendicular magnetic anisotropy constants of the first magnetic layer, second magnetic layer, third magnetic layer, and fourth magnetic layer are Ku1, Ku2, Ku3, and Ku4 respectively, relationships of Ku4>Ku3>Ku2 and Ku1>Ku3>Ku2 are satisfied.
Claims4
A perpendicular magnetic recording medium, comprising:
- a non-magnetic base, and
- a magnetic recording layer on the non-magnetic base, wherein the magnetic recording layer comprises a first magnetic layer, a first exchange coupling control layer, a second magnetic layer, a third magnetic layer, and a fourth magnetic layer, in that order, wherein when the perpendicular magnetic anisotropy constants of the first magnetic layer, second magnetic layer, third magnetic layer, and fourth magnetic layer are Ku1, Ku2, Ku3, and Ku4 respectively, relationships of Ku4>Ku3>Ku2 and Ku1>Ku3>Ku2 are satisfied.
Dependencies are inferred from the claim text.