10W GHz-rate Femtosecond All-fiber MOPA System using PCF-based optoacoustically mode-locked fiber laser

By optimizing pump power to 920 mW, we achieve a stable 1.89-GHz, ~960-fs pulse train with 10 mW average power and an SNR of 55 dB, indicating robust high harmonic mode-locking. A 10-m dispersion-compensated fiber broadens the pulse to 5 ps, which is then amplified through a three-stage Yb-Er co-doped fiber system, resulting in 10.8 W average power and 5.7 nJ per pulse.

The amplified pulse is compressed to 84 fs via higher-order soliton self-compression in a 3.3 m single-mode fiber, achieving a peak power of 1.5 kW and a quality factor of ~22%. This all-fiber laser system provides high average power, high repetition rate, and ultrashort pulse durations, enabling flexible high-power pulse generation for ultrafast applications.