Method and apparatus for magneto-optical recording of a plurality of discrete levels

摘要

The invention provides a medium and a method suitable for magneto-optical and multiple recording. The medium includes alternate thin layers of a magnetic rare-earth metal and an electrically conductive material, and has "magnetic frozen state" at low temperature. The medium may be magnetized to different ferromagnetic states when heated to different temperatures by a controlled laser beam, under an external magnetic field. The different magnetic states permit of multiple recording.