Abstract

We propose the use of frequency upconversion for time division demultiplexing. Suppose we receive an N-channel signal at frequency f1 and make a local short-pulse laser at frequency f2 have the same repetition rate as one of the channels. Mixing them properly in a nonlinear crystal, we can upconvert only one channel to frequency f3 = f1 + f2. We can demultiplex N channels by N such units. The frequency upconversion is a very fast (femtosecond domain or 10E5 GHz) and a low noise process. We show that nearly 80% conversion efficiency of 1.3-0.58 μm can be expected for 50-W peak power pumping at 1.06 μm in a 3-mm long barium sodium niobate crystal.¹ The use of waveguide structure or high nonlinear organic materials may relax the pumping power requirement substantially.

© 1988 Optical Society of America