Influence of the Recording Layer Temperature on Carrier-to-Noise Ratio of Magneto-Optical Disk

The temperature of recording layer during read-out was calculated for some quadrilayer magneto-optical disks and the relation of carrier-to-noise ratio with figure of merit at this temperature was investigated at the wavelength of 532 nm. There have been found that the recording layer temperature has been more influential to carrier-to-noise ratio than the figure of merit, which indicates that temperature has other effects on CNR than reducing Kerr rotation angle and Kerr ellipticity. Practically, the recoding layer temperature can be adopted as a key parameter in improving carrier-to-noise ratio and we have got CNR of 49.1 dB at the wavelength of 532 nm.