20 nm domain expansion readout by magnetic amplifying MO system (MAMMOS)

Very small domains are recorded on the MAMMOS disk and they ran be detected using RF readout field. The MO signal amplitude of 20 nm domains can be enhanced to the saturated signal level. For these small domains, the thermal stability problem is investigated. Even if high laser power for readout is irradiated to the small domains, the reproduced signal was maintained. The result indicates that the recording layer of TbFeCo possesses an advantage for paramagnetic limit problem over 100 Gbits/in/sup 2/.