Simulation study of mid-infrared supercontinuum generation in Ge23Sb12S65-based chalcogenide photonic crystal fiber

We conducted a numerical study of mid-infrared (MIR) supercontinuum (SC) generation with femtosecond pulses in Ge23Sb12S65 chalcogenide photonic crystal fiber (PCF). This PCF has multilayer air holes in the cladding region, which renders its flexibility for controlling the dispersion and confinement loss of the fiber. The broad and flat dispersion profiles and the low confinement loss of the designed PCF combined with the wide MIR transparent window of Ge23Sb12S65 chalcogenide glass largely contributed to the broadband MIR SC generation. Owing to the ultra-high nonlinearity of the designed Ge23Sb12S65 PCF, an ultra-broadband SC ranging from 1.9 μm to 9.3 μm was obtained in a 15 cm fiber by applying a very low pump power of 165 W at 3.3 μm wavelength.