Multi-gas spectroscopy using tailored mid-IR dispersive wave generated in Si3N4 waveguide

We demonstrate simultaneous detection of acetylene, methane and ethane using milliwatt-level dispersive-wave generated in a Si3N4 waveguide covering 2900 cm-1 -3380 cm-1 spectral region. This simple mid-IR absorption spectroscopy scheme achieves hundreds of ppm detection limit.