Opt Lett. 2023 Feb 1;48(3):676-679. doi: 10.1364/OL.478137.
The high power all-solid-state continuous wave single-frequency laser is a significant source for science and application due to good beam quality and low noise. However, the output power of the laser is usually restricted by the harmful thermal lens effect of the solid gain medium. To address this issue, we develop a self-mode-matching compact all-solid-state laser with a symmetrical ring resonator in which four end-pumped Nd:YVO laser crystals are used for both laser gain media and mode-matching elements. With this ingenious design, the thermal lens effect of every laser crystal can be controlled and the dynamic of the designed laser including the stability range and the beam waist sizes at crystals can be manipulated only by adjusting the pump power used on each laser gain medium. Under an appropriate combination of pump powers on four crystals, self-mode-matching in a resonator is realized. A stable CW single-frequency at 1064 nm with 140-W power, 102-kHz linewidth, and low intensity noise is obtained. The presented design paves an effective way to further scale-up the output power of a compact laser by employing more pieces of gain media.
高功率全固态连续波单频激光器由于光束质量好、噪声低，是科学和应用的重要光源。然而，激光的输出功率通常受到固体增益介质有害热透镜效应的限制。为了解决这个问题，我们开发了一种具有对称环形腔的自模式匹配紧凑型全固态激光器，其中四个端面泵浦 Nd：YVO 激光晶体既是激光增益介质又是模式匹配元件。通过这种巧妙的设计，可以控制每个激光晶体的热透镜效应，并且可以通过调节每个激光增益介质上使用的泵浦功率来控制包括稳定性范围和晶体处光束腰尺寸在内的设计激光的动态。在四个晶体的适当泵浦功率组合下，实现了腔内的自模式匹配。获得了 1064nm 处 140W 功率、102kHz 线宽和低强度噪声的稳定 CW 单频输出。所提出的设计为通过使用更多的增益介质进一步提高紧凑型激光器的输出功率铺平了有效途径。
