Magnetic recording technology for 10 Gb/Sq and beyond

The simultaneous scaling of the dimensions of magnetic disk recording systems, combined with many improvements in head and media technology, has produced a million fold increase in data density over the last four decades. But soon media grains will be scaled down to a critical volume where their magnetization will flip spontaneously due to thermal agitation. This thermal instability barrier will occur in longitudinal thin film recording disks at densities above 25Gb/Sq. This will force a change in the traditional scaling rules and the introduction of new recording technologies. A much lower ratio of linear bit density to track density and better signal processing will allow longitudinal recording to be extended to >100Gb/Sq. Beyond this point perpendicular recording and patterned media will be required.