SILICA-BASED INTEGRATED OPTIC MACH-ZEHNDER MULTIPLEXER DEMULTIPLEXER FAMILY WITH CHANNEL SPACING OF 0.01-250 NM

A Mach-Zehnder interferometer design is presented for application to WDM/FDM systems. A variety of integrated-optic devices with low loss and low crosstalk, using silica-based waveguides, are demonstrated. MZ interferometers operate as multi/demultiplexers or frequency-selection switches. The channel spacing is determined by the waveguide arm length difference and a spacing range of 1 GHz-37 THz, corresponding to a wavelength spacing of 0.008-250 nm, is achieved. The devices for the WDM region have low fiber-to-fiber losses of 0.5 dB and the devices for the FDM region have higher losses of 25 dB. Crosstalk of less than -15 dB was obtained for all the devices. A 5 GHz spaced 16-channel frequency selection switch and a 10 GHz spaced eight-channel multi/demultiplexer are also fabricated with a total loss of 5 dB and total crosstalk of -10 dB or less. © 1990 IEEE