PURPOSE: To accelerate the transfer to an equil. phase in the erasing stage of information and to permit high-speed erasure of the information by laminating a photoconductive film on a recording film.

CONSTITUTION: The photoconductive film 9 is provided on the recording film 7 and a conductive reflection film 11 is provided on the photoconductive film 9. The photoconductive film 9 is formed by laminating a photoconductive material such as As2Se3, CdSe or CdS which generates electron-hole pairs when irradiated with a laser beam and does not induce a phase change to about 500W10,000 thickness on the recording film 7. The photoconductive material such as As2Se3 has good sensitivity to the laser beam and the holes (positive charge) among the electron-hole pairs generated in the photoconductive film 9 are implanted into the recording film 7 by the laser beam in the erasing stage. The transfer of the recording film 7 to the equil. phase is thereby accelerated and the high-speed erasure of the information is made possible.