NEW CONCEPTS FOR PERPENDICULAR MAGNETIC RECORDING HARD DISK SYSTEM

New concepts for perpendicular magnetic recording are proposed. Recording mechanism analysis, head-to-media interface and a narrow track single-pole head are described. A finite-element method simulation, with accurate medium modelling, estimates densities over 20 kFRPM (500 kFRPI). The conditions to attain high linear density are revealed quantitatively. Coercive force dispersion of the medium and head-to-medium spacing are key factors. To realize extremely narrow spacing we have proposed contact recording, that is, a non-flying head even for hard disk systems. Using this new head-to-medium interface, a very narrow track single-pole head, 6-mu-m in width, is investigated. The single-pole head can be prepared with control of the domain structure by a wall pinning method. We have found that the normalized output increases as the track width decreases. The signal-to-noise ratio of a 6-mu-m-track-width single-pole head is about 35 dB at low density. The 10(-9) error rate is obtained at 4 kFRPM (100 kFRPI) with a equalizer for read channel.