Abstract

During the last few years we have suggested¹⁻² the use of a four-level system irradiated by a bichromatic beam to obtain a tunable optical bistable device. By tunable we mean that the switching threshold can be altered without changing the hardware characteristics, the operating temperature, or the frequencies of the inputs to the device. The basic principle of our suggestion is that by irradiating the non-linear optical material by two beams of appropriately chosen frequencies in an optical cavity, one can act as a signal and the other as tuning control beam. The advantage of the four level system lay in the possibility of using low power control beams which could tune the characteristic optically bistable output curves.

© 1989 Optical Society of America