A nonlinear-material-based all-optical switching mechanism is utilized to develop the optical flip-flop. As flip-flops are sequential logic circuits, the present state of outputs is dependent on both the present inputs as well as the past outputs. In our present scheme, the outputs are fed back to the former stages instead of the input stages. The output ¯Q and its complemented are obtained simultaneously in our scheme.
Shantanu Kr. Dhar,
"All-optical implementation of S-R, clocked S-R, and D flip-flops using nonlinear material," Optical Engineering 47(6), 065401 (1 June 2008). https://doi.org/10.1117/1.2948348