Operating margins for magneto-optic recording materials with direct overwrite capability

The possibility of achieving direct overwrite in magneto-optic thin films is demonstrated. By using films having a compensation temperature tens of degrees higher than room temperature, writing and erasing of domains thermomagnetically can be accomplished in the absence of a magnetic field The device operating margins were measured in GdTbCo and TbFeCo films, and it was found that write and erasure pulses have wide margins in duration and amplitude while the ambient temperature is varied from room temperature to 80 °C. Data rates higher than 10 MHz are shown feasible with this direct overwrite scheme.