Near-field optical data storage

A recently developed near-field optical technique, the solid immersion lens (SIL), is utilized in a realistic demonstration of near-field optical data storage. Using 830 nm light, a 360 nm optical spot size is obtained at the exit surface of the SIL and is transferred across a small air gap to the surface of a spinning magneto-optical disk. Reading and writing of data are achieved at a density of 3.8× 108 bits/cm2 with a data rate of 3.3×106 bits/s. The subwavelength gap between the lens and the disk is maintained at a media velocity of 1.25 m/s by incorporating the lens into an air-bearing slider.