85-W Burst-Mode Pulse Fiber Amplifier Based on a Q-Switched Mode-Locked Laser With Output Energy 0.5 mJ per Burst Pulse

We report a compact 85-W burst-mode pulse fiber amplifier seeded by a Q-switched mode-locked laser at 1064 nm. At a repetition rate of 154 kHz, the pulse duration of the burst is 4 μs containing 280 of 20-ps pulses with temporal space of ~14 ns, and the total burst energy is about 552 μJ per pulse. The pulse number and the burst repetition frequency can be adjusted from 121 to 154 kHz through increasing the pump power of the seed laser. To the best of our knowledge, this is the first time to observe this type burst pulse amplifier based on the Q-switched mode-locked seed laser. No significant amplified spontaneous emission and stimulated Raman scattering were observed in our experiment when the output power is less than 85 W.