Xiaodan Dou

Repetitively Q-switched laser operation of a miniature Yb:LuPO 4 crystal rod

We report on efficient repetitively Q-switched laser operation of a miniature Yb:LuPO4 crystal rod with emission wavelengths ranging from 1000 to 1010 nm, at different repetition rates over a range of 1−50 kHz. An average output power of 6.55 W was produced at 50 kHz of repetition rate, with a slope efficiency of 40%; in a low-repetition-rate operation at 2 kHz, the maximum pulsed output power generated was 1.43 W, with pulse energy, duration, and peak power being, respectively, 0.715 mJ, 12.5 ns, and 57.2 kW.

Passive Q-Switching of a Yb:LuVO4 Laser with Cr4+:YAG: Approaching the Intrinsic Upper Limit of Repetition Rate

We demonstrate a diode pumped Yb:LuVO 4 laser that can be passively Q-switched by a Cr 4+ :YAG saturable absorber having an initial transmission as high as 99.3%. A maximum pulsed output power of 2.35 W is generated at a repetition rate of 285.7 kHz, approaching or very near the intrinsic upper limit imposed by the recovery time of the Cr 4+ :YAG saturable absorber, and the resulting pulse energy, duration and peak power are, respectively, 8.2 μJ, 39.2 ns and 0.209 kW.

Anisotropy in spectroscopic and laser properties of Yb:Sr 3 La 2 (BO 3 ) 4 disordered crystal

We report, for the first time to our knowledge, on the polarized absorption and emission spectra and efficient laser action of the Yb:Sr3La2(BO3)4 disordered crystal. The strongest absorption and emission occur at about 977 nm for polarization direction parallel to the crystallographic b axis, with the peak absorption and emission cross-sections amounting, respectively, to 1.95 × 10−20 and 2.45 × 10−20 cm2. Efficient continuous-wave laser action is demonstrated with a-, b-, and c-cut crystal samples longitudinally pumped by a 976-nm diode laser, producing an output power of up to 8.2 W with an optical-to-optical efficiency of 32% with respect to incident pump power. Depending on the output coupling utilized, the laser action could exhibit a transition from single-polarization oscillation to dual-orthogonal-polarization oscillation at a certain pump level.