The use of nonlinear optical techniques for the temporal processing of information encoded as envelopes on electromagnetic fields is discussed. Applications using these all-optical interactions in the areas of signal processing, radar, and communication systems are considered and compared with existing approaches.
T. R. O'Meara,
"Time-Domain Signal Processing Via Four-Wave Mixing In Nonlinear Delay Lines," Optical Engineering 21(2), 212237 (1 April 1982). https://doi.org/10.1117/12.7972888