High-performance ultrafast pulse compression in the visible spectral range for extreme nonlinear optics at kHz-MHz repetition rates

We demonstrate a remarkably effective single-stage compression technique for ultrafast pulses in the visible electromagnetic spectrum using second-harmonic pulses at 515 nmderived from a 1030 nm Yb-based femtosecond regenerative amplifier. By employing an advanced multi-plate scheme, we achieve more than fourfold compression from 180 fs to 40 fs with an extremely high spectral broadening efficiency of over 95%, and a temporal compression efficiency exceeding 75%. In addition, our method leverages a low nonlinearity medium to attain the shortest pulse durations for a single compressor while maintaining a superb spatial beam quality with 97% of the energy confined in the main lobe of the Arie disk. Moreover, our technique enhances the temporal pulse quality at 515 nm without generating substantial femtosecond-to-picosecond pulse pedestals. The resulting intense visible laser pulses with excellent spatio-temporal parameters and high repetition rate of 100 kHz to 1 MHz open up new frontiers for extreme nonlinear optics and ultrabright EUV and X-ray high-harmonic generation using short VIS wavelength.