Mid-infrared Sensing with Ge on Si Waveguides

Abstract

Ge-on-Si waveguides with losses below 5 dB/cm across 7.5 to 11 µm wavelength are demonstrated. Sidewall etch roughness was measured using atomic force microscopy to investigate the waveguide loss mechanisms. Mid-infrared spectroscopy of poly(methyl methacrylate) was demonstrated using the Ge waveguides for mid-infrared sensing.