Yaoyao Qi

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

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.

Output characteristics of diode-end-pumped electro-optically Q-switched Nd:LuVO4 laser at 1064 nm

Abstract. We demonstrated a Q-switched Nd:LuVO4 laser with fundamental mode at 1064 nm using BaB2O4 electro-optic Q-switching. High-efficiency operation of Q-switched laser with dynamic to static ratio of 91.4% was realized. When the absorbed pump power was 6.59 W, the maximum average output power of 2.88 W was achieved with a repetition rate of 50 kHz. The optical conversion efficiency and slope efficiency were 43.7% and 55.5%, respectively. The minimum pulse width of 17.8 ns was achieved. Meanwhile, the pulse energy and peak power were 57.6  μJ and 3.2 kW, respectively. To the best of our knowledge, this study is the first to demonstrate about the electro-optically Q-switched laser in Nd:LuVO4 crystal.

Generation of 130 W narrow-linewidth high-peak-power picosecond pulses directly from a compact Yb-doped single-stage fiber amplifier

Abstract. We report a compact, 130-W single-stage master oscillator power amplifier with a high peak power of 51.3 kW and a narrow spectral linewidth of 0.1 nm. The seed source is a single-mode, passively mode-locked solid-state laser at 1064 nm with an average power of 2 W. At a repetition rate of 73.5 MHz, the pulse duration is 30 ps. After amplification, it stretches to 34.5 ps. The experiment enables the optical-to-optical conversion efficiency to reach 75%. To the best of our knowledge, this is the first report of such a high-power, narrow spectral linewidth, high peak power picosecond-pulse fiber amplifier based on a continuous-wave, mode-locked solid-state seeding laser. No amplified spontaneous emission and stimulated Raman scattering were observed when the pump was increased.

152 W high-power blue diode laser operated at 447 nm

We demonstrate a high-power blue diode laser operated at 447 nm combining laser diodes using an optical fiber bundle. As many as 127 diode lasers at 447 nm were coupled into 400 μ m/0.22NA fibers using an aspherical lens group with different focus lengths. The bare fibers were mechanically bundled through high temperature ultraviolet adhesive after the coatings of the 127 fibers were stripped. The diameter of the fiber bundle was 6 mm. The total output power of such a bundle was 152 W with electro-optical conversion efficiency of 27.56% and the RMS power instability was less than ± 1% within 3 h.