Magnetic recording media with write-assist layer

Abstract

A magnetic recording disk has a ferromagnetic recording layer and a “paramagnetic” write assist layer in contact and exchange coupled with the ferromagnetic recording layer. The write assist layer is a ferromagnetic material that has a Curie temperature less than the operating temperature of the disk drive so that at operating temperature and in the absence of a write field, the write assist layer is in its paramagnetic state and has no remanent magnetization. When a write field is applied in a direction opposite to the magnetization in previously written regions of the ferromagnetic recording layer, the write assist layer exhibits a magnetization aligned with the write field and assists the write field in reversing the magnetization in the ferromagnetic recording layer due to the exchange coupling. The write assist layer allows higher anisotropy materials to be used in the ferromagnetic recording layer, which results in improved media thermal stability, because it reduces the effective anisotropy of the ferromagnetic recording layer during writing.

Dependencies are inferred from the claim text.