Four-channel Ti:LiNbO(3) wavelength division multiplexer for 1.3-microm wavelength operation

A four-channel Ti:LiNbO(3) wavelength division multiplexer (WDM) that uses cascaded two-mode-interference dual-channel WDM waveguide structures was demonstrated. Its implementation in integrated-optic form affords ease of fabrication, voltage tunability, and the potential for combining other devices for different functions on the same chip. The device was operated in the wavelength region of 1.3 microm. The channel spacings ranged from 12 to 15 nm. The channel wavelengths can be electro-optically tuned at the rate of 1 nm/V. The cross talk was measured to be less than -20 dB.