Magnetooptical beam addressable storage using MnGaGe and GdCo

The discovery of MnGaGe and GdCo, room-temperature magnetooptical materials, and their fabrication in thin-film form has led to experiments on high-areal-density high-data-rate optical storage of digital data. The results of read/write experiments using 77 K GaAs lasers will be presented and briefly discussed. Calculation of the ultimate performance in terms of areal density for a given signal-to-noise ratio as a function of material figure of merit, detector bandwidth, and detector quantum efficiency will be reviewed and discussed giving experimental data for MnGaGe and GdCo. This will be compared with predicted performance for conventional inductive magnetic recording.