Abstract
A magneto-optical (M-O) disk for readout using the circular dichroism effect was investigated. With this method, the optical head can be simplified because recorded bits are directly detected as the intensity change of reflected light. We studied multi-layer structure films in order to enhance the circular dichroism effect and found a preferable quadrilayer structure M-O medium consisting of AlN, GdTbFe, AlN and Al. The read-out signal quality was evaluated with the optical head and we achieved a 45 dB carrier-to-noise ratio at 1.3μm bit length.
