Chen Peining, Xiao Zefeng, Guo Chuan, Tan Weifeng, Chen Rongzhuo, Dai Shibo, Zhu Siqi, Yin Hao, Li Zhen, Chen Zhenqiang
Opt Express. 2025 Jul 28;33(15):31334-31343. doi: 10.1364/OE.570338.
A high-beam-quality nanosecond pulsed pro-yellow laser is demonstrated based on an acousto-optically -switched intracavity frequency-doubled KGW Raman laser driven by the 1053 nm Nd:YLF laser on the σ polarization. Compared to the π-polarization emission of Nd:YLF crystal, the σ-polarization emission induces a weaker thermal lensing effect, thereby enhancing both the beam quality and thermal stability of the pro-yellow laser without requiring additional optical compensation elements. Two distinct first-Stokes lasers at 1146 and 1164 nm are produced benefiting from the bi-axial properties of KGW crystal, and subsequently frequency-doubled to 573 and 582 nm via a critically phase-matched LBO crystal. Both experimental results and theoretical analysis manifest that the decreased gate-open time within the microsecond range can increase the nonlinear conversion efficiency. Under the incident pump power of 36.9 W and the duty cycle of 1%, the maximum average powers reach 2.5 and 3.4 W with the pulse durations of 8.3 and 7.6 ns at the repetition rate of 5 kHz, respectively. Additionally, at the repetition rate of 1 kHz, the pulse energies are elevated to 2.0 and 2.8 mJ with the pulse durations of 6.2 and 5.3 ns, respectively, corresponding to the peak powers of 323 and 533 kW. The factor maintains below 1.6 across the entire output power range.
基于由1053 nm Nd:YLF激光在σ偏振下驱动的声光开关腔内倍频KGW拉曼激光器，演示了一种高光束质量的纳秒脉冲准黄色激光器。与Nd:YLF晶体的π偏振发射相比，σ偏振发射引起的热透镜效应较弱，从而在无需额外光学补偿元件的情况下提高了准黄色激光器的光束质量和热稳定性。得益于KGW晶体的双轴特性，产生了1146和1164 nm的两种不同的一阶斯托克斯激光器，随后通过临界相位匹配的LBO晶体倍频至573和582 nm。实验结果和理论分析均表明，在微秒范围内减小门开时间可提高非线性转换效率。在36.9 W的入射泵浦功率和1%的占空比下，在5 kHz的重复频率下，脉冲持续时间分别为8.3和7.6 ns时，最大平均功率分别达到2.5和3.4 W。此外，在1 kHz的重复频率下，脉冲能量分别提高到2.0和2.8 mJ，脉冲持续时间分别为6.2和5.3 ns，对应峰值功率为323和533 kW。在整个输出功率范围内，该因子保持在1.6以下。
