Chirped waveguide gratings for low-cost silicon photonic wire packaging and other applications

Abstract

We review our recent work on chirped waveguide gratings for efficient coupling between standard single mode optical fibers and silicon photonic wire waveguides. The use of a linear chirp in grating period reduces the second order Bragg reflection from the waveguide gratings and increases the coupling efficiency for perfectly vertical optical fibers. Measurement results obtained from devices fabricated using deep UV lithography yielded coupling efficiencies of over 34%. Techniques to further improve the coupling efficiency will be discussed. The use of chirped waveguide gratings for low cost photonic packaging and the application of waveguide gratings for splitting/combining light will also be presented.