Binary Super Grating (BSG) Self-Collimated Multi-Wavelength Laser

This project concerns the exploration of two novel and enabling technologies a self-collimated multi-wavelength laser SCMWL, and the underlying binary superimposed grating BSG, on which the SCMWL depends. The BSG is a multi-wavelength reflector which can be implemented by a convenient two-level etching process. The SCMWL makes use of BSGs to form a planar cavity with collimated multi-wavelength resonances. When combined with gain, the result is self-collimated multi-wavelength output. We have demonstrated for the first time that both the BSG and the SCMWL concept work, through three proof-of-concept implementations in an optically pumped AlGaAs planar waveguide. These simplest-case devices exhibit multi-wavelength lasing at as many as 4 wavelengths, with channel spacings in accord with prediction. These preliminary results call for more exhaustive characterization, and pave the way for the implementation of electrically pumped SCMWLs with a greater number of wavelengths.