High-Efficiency SOI Fiber-to-Chip Grating Couplers and Low-Loss Waveguides for the Short-Wave Infrared

We report on high-efficiency silicon-on-insulator (SOI) grating couplers and low-loss single-mode optical waveguides operating in a short-wave infrared. A -3.8 dB coupling efficiency from a standard single-mode fiber to an SOI waveguide at 2.1 μm is obtained experimentally. Single-mode waveguide losses in the short-wave infrared below 0.6 dB/cm are reported.