連続媒体ノイズ要因の一考察

Abstract

Possibility to decrease signal recorded noise of metal thin-film media by decreasing magnetic coupling between crystallites was studied with the following results. 1) Reverse DC erase noise is strongly related to signal recorded noise. 2) Reverse DC erase noise characteristics show a positive peak metal thinfilm media which have strong magnetic coupling between crystallites. 3) Contrarily, they show a negative dip particulate media which have weak coupling between magnetic particles. A Co-Cr thin-film medium and an isotropic anisotropy particulate medium are selected as a medium which has weaker magnetic coupling than a metal thin-film medium and a Co-γ sputtered medium with a peak in reverse DC erase noise characteristics, respectively. Reverse DC erase noise characteristics of these two media show a dip. As expected from the above results, signal recorded noise of a Co-Cr medium decreases slightly and that of an isotropic particulate medium also decreases as the recording density increases. Thus the possibility to decrease signal recorded media noise of metal thin-film media by decreasing magnetic coupling is confirmed.