Simulation Study of Effect of Dispersions on Recording Performances in Perpendicular Magnetic Recording Media

Effect of dispersions of medium parameters and structure on the recording performance was systematically investigated. Moderately increased M-H loop slope is effective for obtaining higher thermal stability, smaller saturation fields, and higher resolution. It was found that the most influential factor is the dispersion in anisotropy field, H k . Small H k dispersion reduced the noise when exchange coupled media were used. Reduced grain size and a stacked structure of the media were expected to give a restricted gain in the signal to noise ratio.