Overview of read/write scheme for perpendicular magnetic recording utilizing single-pole head and double layer media

Head/media parameters of perpendicular magnetic recording to attain areal densities of 100-200 Gbits/in² were investigated. Shield gap length, medium thickness, magnetic spacing, and transition width to realize the required PW₅₀ for the densities were described first. Then, for the derived head/medium condition, maximum magnetic cluster size of the medium to satisfy medium noise requirements was predicted from experimental results and a theoretical noise consideration. Finally, minimum anisotropy energy for the medium to resist thermal signal decay was also considered. Results indicated that magnetic cluster average size, which was defined as magnetically grouped grains, and media anisotropy fields were to be 10nm and 19 kOe, respectively, in order to attain 200 Gbits/in² recording. A new media structure to resolve the dilemma of media noise and thermal stability was also described.