Domain expansion readout system with DC magnetic field

MAMMOS (Magnetic Amplifying Magneto Optical System) is a technique for realizing high-density magneto-optical disk. Conventional MAMMOS readout process needs AC magnetic field for expanding and erasing magnetic domains. As a new readout system, MAMMOS readout that needs only DC magnetic field using RE (Rare-Earth)-rich GdFeCo readout layer was developed. This method exhibited a high readout resolution in spite of an AC field-free method.