RECORDING SYSTEM WITH MAGNETO-OPTIC LAYERS, MAGNETO-OPTIC RECORDING SYSTEM AND WRITING PROCESS

摘要

A recording system with magneto-optic layers has a magnetic layer for recording digital information. The recording system has two or three ferromagnetic layers with intermediate semiconducting layers. The ferromagnetic layers are magnetised with different degrees of hardness. The thickness and band gap of the semiconducting layers are sized so that a sufficient number of electrons capable of being excited by photo-induction may be excited in the hitherto empty conduction band states of the semiconductor by a focused beam emitted by a source of light of appropriate intensity and wavelength. An RKKY-type coupling is thus created between adjacent ferromagnetic layers which would not exist in the absence of light. This coupling causes information to be recorded in or erased from one of the ferromagnetic layers. Also disclosed is a magneto-optic recording system with recording layers and writing head, light source and focusing system. This recording system makes a particularly rapid writing process possible.