HIGH DENSITY MAGNETO-OPTICAL RECORDING MEDIUM CAPABLE OF OVERWRITING AND RECORDING OR REPRODUCING METHOD

摘要

PURPOSE:To provide a magneto-optical recording medium capable of optical modulated direct overwriting and also capable of reproduction with super- resolution and a recording or reproducing method for the recording medium. CONSTITUTION:This magneto-optical recording medium has six magnetic layers laminated while bonding the adjacent magnetic layers by exchange power. The 1st magnetic layer 1 is made of a ferromagnetic substance contg. a rare earth element-transition metal alloy or a magnetic transition metal and each of the other magnetic layers 2-6 is made of a rare earth metal-transition metal alloy. Each of the magnetic layers 1-6 has a specified Curie temp. and the 1st to 3rd magnetic layers and the 4th to 6th magnetic layers are uniform in the magnetization direction of the sub-lattices of the transition metal at room temp (including a magnetization direction in the first layer). In the case of recording or reproduction, the direction of an external magnetic field impressed at the time of recording and that impressed at the time of reproduction are made to coincide with each other.