Compact 10 MHz, 140 MW peak power source enabling bright high harmonic generation

Employing a gas-filled Kagome fiber for nonlinear post-compression of a compact 8.5 µJ, 250 fs fiber laser system yields 7 µJ, 30 fs pulses at 76 W average and 140 MW peak power. The unique potential of this concept is corroborated by enabling directly laser-driven phase-matched high harmonic generation at 10 MHz repetition rate for the first time.