Magnetic properties, magnetic cluster size, and read-write performance of CoPtCr-SiO/sub 2/ perpendicular recording media

Abstract

The characteristics of CoPtCr-SiO 2 perpendicular media were investigated, especially focusing on the dependence of magnetic properties and read-write performance on magnetic cluster size.increases with reducing magnetic cluster size. As magnetic cluster size decreases, media noise and signal-to-noise ratio are improved and magnetic write width becomes narrower, indicating that reducing the magnetic cluster size is an effective means to increase both bit and track densities. However, diminution of magnetic cluster size degrades thermal stability. Lowering the magnetic cluster size threshold, above which a medium is thermally stable, is necessary in order to obtain a low noise and thermally stable medium.Index Terms-CoPtCr-SiO 2 , magnetic cluster size, media noise, perpendicular recording media, thermal stability.

Effects of sub-domain structure on initial magnetization curve and domain size distribution of stacked media

“…The domain size was measured as follows. It is based on a method of measuring domain size by approximating magnetic domain shape with a circle [10]. As shown in Fig.…”

High-performance CoPtCrO perpendicular media: optimizing exchange coupling and anisotropy orientation dispersion

“…Previous works on CoPtCr-SiO 2 media deposited on a Ru underlayer showed that exchange coupling can be varied depending on the thickness or deposition condition of the Ru underlayer [4,7]. In this work, the exchange was systematically varied by controlling the Cr-O grain boundary segregation.…”

Improvement of magnetic intergranular isolation and evaluation of read/write characteristics on SmCo5 perpendicular magnetic thin films

“…Since large magnetic domains cause a considerable amount of medium noise, it is necessary to decrease the intergranular exchange interaction in order to apply SmCo 5 thin films to practical media [17,18].…”