Integrated optics N*N multiplexer on silicon

The authors report the measured performance of an integrated N*N multiplexer fabricated using SiO/sub 2//Si waveguides. The insertion loss for N=7 was typically lower than 2.5 dB, and crosstalk was less than -25 dB. The multiplexer response is approximately periodic. In each period the multiplexer accepts, from each input waveguide, a total of N channels, and it efficiently transmits each channel to a particular output port. Similarly, each output port receives N channels, one from each input port. Thus, the total number of channels that can be transmitted simultaneously is N/sup 2/, which requires N optical frequencies.>