Writability enhancement using exchange spring media

Longitudinal exchange-spring media, which consist of a low anisotropic (soft) layer (CoCrX) on top of a high anisotropic (hard) layer (CoPtCrB) separated by a ferromagnetic coupling layer (CoRu), was evaluated. It is found out that this structure has improved writing properties as well as an increased signal while maintaining signal to noise ratio (S/sub 0/NR) in longitudinal antiferromagnetically-coupled (AFC) media. The magnetization versus field loop was obtained using SQUID magnetometer. The recording performance was also evaluated using a Guzik spinstand.