Mid Infrared supercontinuum generation in a silicon germanium photonic waveguide

Abstract

We report simulations of pulse evolution along a 5 cm long silicon germanium (SiGe) photonic waveguide. Femtosecond laser pulses of duration 210 fs and wavelength of 4.7 µm close to the first zero dispersion wavelength (ZDW) of SiGe situated at 4.6 µm were used in pumping the SiGe photonic waveguide. Simulations were made by solving the generalised nonlinear Schrödinger equation for the femtosecond pump pulse evolution along the length of SiGe photonic waveguide using the fourth order Runge-Kutta in the interaction picture method. The simulated supercontinum spans the 2.5–8.5 µm spectral region comprising of molecular signatures for most hazardous and greenhouse gases making it attractive for environmental monitoring applications.