WRITE ERASE CYCLABILITY OF TBFECO FOR MARK EDGE RECORDING

Domain size changes due to thermal relaxation after high laser power i rradiation on amorphous TbFeCo films were studied. In order to achieve mark edge recording for high-density magneto-optical memory, accurate domain size recording is required even after a million erase/write cy cles. Highly accelerated erase/write test was performed on typical rec ording media, rare-earth (RE) -rich and transition-metal (TM)-rich dis ks. The elongation of the domain size written on the TM-rich film afte r erase/write cycles was clearly evident; however, the change in the d omain size of RE-rich films was small. The small domain size change of the RE-rich disk can be explained in terms of the rapid increase in t he coercive force with decreasing temperature and the smaller domain-w all driving force at recording temperature than those for the TM-rich disk, even though both have the same level of structural relaxation.