The motivation for the development of all-optical logic elements in integrated optical waveguides is reviewed. The difficulties inherent in the ‘all-optical' approach are outlined. The all-optical, universal logic for pipeline operation based on the Mach— Zehnder interferometer is described and experiments on a prototype all-optical modulator fabricated in LiNbO
3
are presented. The paper concludes with a discussion of a device design for operation with shorter lengths and compatible with semiconductor laser drives.
All-Optical Modulation In Gallium Arsenide Integrated Optical Waveguides