基于光参量振荡的35kHz中红外激光器研究

Research on mid-infrared laser at 35kHz based on optical parametric oscillator

研究了基于高重频1 064 nm激光泵浦的3.8μm周期性极化铌酸锂(periodically poled LiNbO, PPLN)光参量振荡器(optical parametric oscillator, OPO)。采用Nd:YVO声光调Q激光器,获得了光束质量良好,重复频率25~35 kHz,最大平均输出功率6.1 W,脉冲宽度59.1 ns的1 064 nm基频激光。模拟分析了在1 064 nm激光泵浦下,极化周期Λ=29.5μm MgO:PPLN晶体的温度调谐特性。通过实验,在25~200℃的温度范围内,获得了3 599.6~3 845.5 nm连续变化的中红外激光。当PPLN晶体温度为30℃,基频光功率为6.1 W时,得到了最大输出功率0.45 W,重复频率为35 kHz的3 845.5 nm中红外光输出。

A 3.8 μm periodically poled LiNbOoptical parametric oscillator based on high repetition frequency pumping is studied. The Nd:YVOacousto-optic Q-switched laser is used, obtaining a fundamental1 064 nm laser with good beam quality, the repetition frequency at 25-35 kHz, the maximum average power of 6.1 W and the pulse width of 59.1 ns. The temperature tuning characteristic of MgO:PPLN crystal with the periodΛ=29.5 μm under the 1 064 nm laser pumping is simulated. Through experiments, the 3 599.6-3 845.5 nm mid-infrared laser is obtained at a temperature of 25-200 ℃. When the temperature of the PPLN crystal is 30 ℃and the pump power is 6.1 W, the mid-infrared laser is obtained with the maximum output power of 0.45 W and the repetition frequency of 35 kHz at 3 845.5 nm.