Abstract

In the past few years interest has arisen theoretically and experimentally in realizing a first-order phase transition behavior, i.e., bistability in conventional lasers that usually display a second-order phase-transition character.^1,2 Though some works involved the observation of a bistability or hysteresis effect in gas, dye, and semiconductor lasers, they are likely to be quite far from capability as key elements for the optical system in integrated structures. From this point of view, we have recently reported the operational principle and experimental demonstration of novel types of active bistable optical sources named bistable laser diode (BILD)³ and bistable light-emitting diode (BILED)⁴ consisting simply of a laser diode (LD) or a light-emitting diode (LED) and a photodetector (PD). These devices have attractive features that monolithic integration can be achieved without any difficulty using various semiconductor laser materials. As further extension, we describe new configurations and operations of basic optical logic functions that can be achieved with these integrated optical devices.

© 1984 Optical Society of America