High-power femtosecond pulses fiber laser system

High-repetition-rate high-power femtosecond pulses are urgently needed for the development of both scientific research and hyperfine industrial processing. In this paper, chirped pulsed amplification method was used to generate high-repetition-rate high-power ultrashort pulses. Yb-doped large-mode-area double-clad photonic crystal fiber was employed as the gain medium due to the near diffraction limit beam quality as well as the excellent heat dissipation character. The system included passive mode-locked ultrashort pulse laser oscillator, diffraction grating based stretcher, single mode fiber pre-amplifier, double- clad fiber main-amplifier, and transmission grating based pulse compressor. A repetition rate of 40 MHz with pulse width of 273 fs and average power of 150 W was obtained from the fiber laser system, which was placed on the 3 m×1.5 m optical platform. By further improving, the volume of the system is expected to substantially reduce, and the system will become a powerful tool for scientific research and industrial applications.