We demonstrated a solar-pumped laser with a heliostat–parabolic mirror system. A designed conical pump cavity with a water-filled quartz tube lens was used to couple efficiently the concentrated solar radiation from the focal zone of the primary concentrator into a 5.5-mm-diameter, 95-mm-length grooved Nd:YAG crystal rod within a gold-plated conical pump cavity. For 1.0-m2 effective solar radiation collection area, 20.1-W continuous-wave (CW) output laser power was obtained, corresponding to a total system slope efficiency of 5.04%. This value was 1.31 times higher than the previous with the same solar facility. For 1.5-m2 effective collection area, 34.6-W CW output laser power was achieved at the total system slope efficiency of 4.51%. A strong dependency of laser power on laser rod mounting position was also found.
The increase of the numbers of laser channel is beneficial to the improvement of laser communication capacity, and a three-longitudinal-mode Nd:YAG laser with a central wavelength of 1.06 μm is studied. The three-longitudinal-mode continuous-wave(CW) laser output is obtained in 808nm LD-pumped 2.4mm Nd: YAG thin disk with a slope efficiency of 11.65% at 20°, the output power of the CW laser is 11.9mW when the power of the pumping is 365mW, and the frequency spacing is 35.4GHz.The maximum output power of 60.3mW is obtained under the 801mW pumped power. The longitudinal mode gain competition is verified in the experiment and the three-longitudinal-mode laser can maintain a stable output when the pumped power reaches 667mW. With the pump power increases, the frequency of laser output power increases, also accompanied by the phenomenon of frequency drift.