2μm mid-infrared silicon-rich silicon nitride/silicon hybrid nonlinear waveguides

A silicon-rich silicon nitride (SRN)/silicon hybrid waveguide is proposed for 2μm mid-infrared (MIR) nonlinear applications. In the 1950 nm band, the measured linear loss and nonlinear coefficient for TE mode are 18.6 dB/cm and 7.9 W−1m−1, respectively. In a 4-mm-long SRN/silicon hybrid waveguide, the four-wave mixing conversion efficiency reaches −52.3 dB and the 3-dB conversion bandwidth is predicted to be 78 nm when the pump power is only 159 mW. As the nonlinear losses increase with pump power increasing, the nonlinear performance of our hybrid waveguide would exceed that of silicon waveguide when pump power is large and thus our hybrid waveguide is of potential for 2μm MIR nonlinear applications.