Perpendicular magnetic recording

This paper describes the recent studies for the magnetic head, the medium and the recording properties on a new perpendicular magnetic recording system. The complemental features between the perpendicular and the longitudinal recording are discussed to establish an efficient magnetic recording system. Superior response in the amplitude and the peak shift characteristics for a digital signal proves that the perpendicular magnetization mode is basically free from the recording demagnetization in high densities and the maximum density has been limited merely by the resolution of the reproducing head. Significant improvement for the recording and the reproducing sensitivities of a perpendicular head has been made by using a composite anisotropy medium composed by double layers of Fe-Ni and Co-Cr thin films.