STIMULATED ELECTRONIC-TRANSITION CONCEPT FOR AN ERASABLE OPTICAL MEMORY

A new concept for an erasable optical memory is demonstrated using stimulated electronic transition (SET). Large bandgap semiconductors are suitable materials for the SET medium. We have investigated the properties of MgS:Eu, Sm and SrS:Eu, Sm as possible media for the SET process. Quantum storage is achieved in the form of charges in deep levels in the medium and stimulated radiative recombination is used as the reading process. Unlike magneto-optic (M-O) and phase change (PC) processes, optical writing, reading and erasing are achieved without localized heating. The SET process will have an inherently faster data transfer rate and a higher storage density, and the medium will be more durable than the M-O and PC media. A possible application of the SET process in neural networks is also discussed.