Integrated-optic timing tuner for high-speed WDM signals

We demonstrate an integrated-optic timing tuner, which is used for the fine adjustment of wavelength-divisionmultiplexing (WDM) signal delays. This tuner can be utilized to compensate for the bit skew of high-speed WDM bitparallel links in the next generation or to reduce nonlinear effects in WDM transmissions. The tuner consists of an arrayed-waveguide grating and variable delay lines comprising asymmetrical Mach-Zehnder interferometers with different arm lengths. We demonstrate experimentally that our device is capable of accurate delay tuning for 16 *10 to 40-Gb/s systems.