0.5-W Few-Cycle Frequency Comb at 4 μm from an Efficient Simulton-based Optical Parametric Oscillator

We report generation of three-cycle pulses at 4.18 μm with 565-mW average power, 900-nm instantaneous FWHM bandwidth, 350% slope efficiency, and 44% conversion efficiency, based on a half-harmonic optical parametric oscillator operating in simulton regime.