Silicon-on-Nitride Waveguide With Ultralow Dispersion Over an Octave-Spanning Mid-Infrared Wavelength Range

The proposed silicon-on-nitride (SON) waveguide exhibits an ultrabroadband (similar to 4200 nm), low chromatic dispersion (+/- 50 ps/(nm.km)) in the mid-infrared (MIR) wavelength region from 2430 to 6630 nm. It has two zero-dispersion wavelengths within the span. Even at 6 mu m, the nonlinear coefficients of the SON waveguides are still comparable with the ones of integrated Si3N4 waveguides around 1550 nm, which are widely used for octave-spanning nonlinear process. This enables a potential nonlinear optical platform for broadband signal processing across the over-one-octave MIR bandwidth.