Mid-IR waveguides and grating couplers for 2.7-2.9 μm

Integrated silicon photonics strip waveguides and grating couplers are developed for mid-infrared (mid-IR) wavelengths at 2.7 μm and 2.9 μm. Waveguide loss is measured as a function of width for 2.7 μm light in the vicinity of a prominent OH absorption band, and a loss of less than 2 dB/cm is recorded for the 1.0 μm width waveguide. A fabrication bias metric is determined for accurately developing grating couplers at 2.9 μm on a 500 nm silicon-on-insulator (SOI), 3 μm buried-oxide substrate. A high resolution measurement scheme is motivated and measurements indicate that these devices will be capable of studying the Se+ donor spin qubit cavity coupling platform proposed by researchers at Simon Fraser University.