Mid-infrared frequency comb with 25 pJ threshold via CW-seeded optical parametric generation in nonlinear waveguide

We demonstrate efficient generation of mid-infrared frequency combs based on continuous-wave-seeded femtosecond optical parametric generation in nonlinear waveguides. Conversion of the near-infrared pump to signal and idler light takes place with very high efficiency (74%), and the threshold (25 pJ for 100 fs pulses) is over 300 times lower than in bulk analogs. Relative intensity noise of the mid-infrared comb is exceptionally low, below 5 x 10(-5) (integrated from 10 Hz to 2 MHz). Furthermore, the mid-infrared bandwidth can be increased by driving the process with a broadband pump obtained via supercontinuum generation. (C) 2021 Optical Society of America

Automated summary

Efficient generation of mid-infrared frequency combs is demonstrated based on continuous-wave-seeded femtosecond optical parametric generation in nonlinear waveguides. The conversion efficiency of the near-infrared pump to signal and idler light is high, with exceptionally low relative intensity noise in the mid-infrared comb. Additionally, the mid-infrared bandwidth can be increased by driving the process with a broadband pump obtained via supercontinuum generation.