Fundamental Limitations on the Operation of Optical Bistable Devices in a Ring Cavity and in Gallium-Arsenide Etalons.

Shlomo Ovadia

Published Jan 1, 1984• 0 citations

Abstract

The fundamental limitations on the operation of optical bistable devices in a ring cavity and in GaAs etalons are investigated. Experimental results of spontaneous transitions due to shot noise fluctuations are found in good agreement with various "ladder" models, if one allows the counting rates to vary accordingly. Stability analysis for two-photon homogeneously broadened media reveals single-wavelength instabilities for the laser but not for absorptive optical bistability. Appreciable regions of sidemode gain exist for both problems allowing for multiwavelength instabilities to occur. GaAs bistable devices show attractive features such as low power and high speed at room temperature for optical processing. However, experimental evidence in GaAs confirm the computer simulations of bistability that cavity losses, due to unsaturable background absorption, limit the switching power at room temperature. Methods to overcome the different limitations in GaAs devices toward parallel computation are then addressed from a system approach.

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