One of the problems in optical time division multiplexing (OTDM)1 is the lack of a high speed demultiplexer. We propose an optical demultiplexing technique using optical parametric interactions to increase the bandwidth beyond the limit of techniques such as electrooptics switching. Suppose we receive a N-channel signal at frequency f1 and use a local short pulse laser at f2 with the same repetition rate as one of the channels. Mixing them in a nonlinear optical crystal, we can isolate one of the channels by upconversion to a frequency f3 = f1 + f2.2 We can demultiplex N channels by N such units (Fig. 1). Since optical parametric interactions can have a time response of less than a picosecond, such demultiplexers can be made with a bit rate capacity of the order of tera (1012) bits/s.
© 1990 Optical Society of AmericaPDF Article