Multiple wavelength sources, detectors, and routers

As wavelength-division multiplexing (WDM) penetrates deeper into the distribution network, the cost of WDM components becomes an important part of the overall systems cost. Furthermore, the requirements on wavelength accuracy and stability become more stringent as the number of wavelengths is increased. This tutorial will describe an emerging technology that has the potential to deliver both cost-effective WDM components and excellent wavelength control. This new technology is based on the monolithic integration of the passive waveguide grating router (WGR) with active components. It allows us to fabricate WDM building blocks like multifrequency lasers, WDM receivers, or channel add/drop optical filters