Silicon waveguides for the mid-infrared wavelength region

Mid-infrared wavelength region is interesting for several application areas including sensing, communications, signal processing, and imaging. Its importance stems from the two atmospheric windows and the fact that nearly all important molecular gases have strong absorption lines in the mid-infrared. In this paper, we discuss the design, fabrication and propagation loss measurements of three silicon waveguide structures that can find applications in the mid-infrared region.