Optical transistors and bistable devices utilizing nonlinear transmission of light in systems with undirectional coupled waves

An analysis is made of nonlinear transmission (self-switching, self-modulation) of light in tunnel-coupled cubically nonlinear waveguides and other optical systems carrying unidirectional waves with a distributed coupling which become separated at the exit from a system if at least one of the waves travels in a medium with a cubic (Kerr) susceptibility. Optical transistors and bistable devices based on these systems are considered. The threshold energy of bistable devices based on coupled GaAs waveguides is ~10^–10–10^–9 J.