Optical-signal-controlled logic elements for computers

An analysis is made of the operation of an all-optical light switch made from nonlinear waveguides with a distributed coupling. Such a switch is a hybrid of a Mach–Zehnder interferometer and a nonlinear directional coupler. It is shown that the switch can operate at signal powers approximately one-sixth of those needed for a Mach–Zehnder interferometer. An analysis is made of the possibility of using such switches in constructing optical gates controlled by optical signals. The circuit characteristics of such gates are given.