Magneto-optical recording on Pt/Co and GdFeCo/TbFeCo disks using a green laser

The authors report that the Pt/Co multilayer disk and the GdFeCo/TbFeCo double-layer disk have been investigated for high density magneto-optical recording using a low noise and high power green laser. A high carrier/noise (C/N) ratio of 45 dB at a mark length of 0.4 mu m was obtained for both disks with a track pitch of 0.9 mu m. The results show the possibility of areal densities more than three times higher than those of current ISO standard magneto-optical disks. The system noise, the short noise, and the disk noise were measured experimentally as a function of frequency in order to investigate how to improve the C/N ratio using a green laser. >