Abstract
The dependence of erasenoise on magneto-optical (MO) film thickness was studiedin order to clarify the origin of such noise in amorphous TbFeCoTi MO media. Erase noises were measured from the RF differential signals of an MO head, which represented local variations in MO film Kerr rotations. These signal levels were decreased by increasing the MO film thickness and by increasing the SiN under-layer sputter etching. The reductions in noise corresponded to increases in the perpendicular magnetic anisotropy constant Ku for the MO film. Further, higher read power irradiation to MO films with an external bias magnetic field lowered the noise levels drastically. The magnetization fluctuation at the initial layer of the MO film growth was discussed to explain the orlgln of the noises.
