1653 nm光参量放大器及在甲烷遥测方面的应用

基于掺氧化镁的周期性极化铌酸锂（MgO:PPLN）晶体,研究了连续波种子光注入结构的光参量放大器(OPA)。采用重复频率为10 kHz、最大平均输出功率为6 W的1064 nm高频脉冲激光作为抽运源,晶体的极化周期为31.02 m,在119 ℃工作温度下,将连续分布式反馈激光器（DFB）作为种子注入,在1652.3 nm处得到最大平均功率为125 mW的OPA信号光输出,量子转换效率为7.47％。实验通过改变注入种子光波长,实现了信号光nm级范围的调谐输出。信号光通过10 m外甲烷气池,观察到其光谱强度明显下降,初步验证了信号光在甲烷遥测领域的可行性。与用种子光直接检测相比,信号光强度更高,检测距离及灵敏度均有较大优势。

1653 nm optical parametric amplifier and its application in remote sensing of CH4

Based on magnesium oxide-doped periodically poled lithium niobate (MgO:PPLN) crystal, a second-level optical parametric amplifier (OPA) with continuous-wave(CW) laser injection was studied. Pumped by a 10 kHz, 1064 nm, 6 W(the maximum average output power) high-frequency pulse laser and seeded with a low power distributed feedback (DFB) diode CW laser, the OPA obtained a signal at 1652.3 nm and 119 ℃ with the crystal polarization cycle of 31.02 m. The maximum average power of the signal was 125 mW with the quantum conversion efficiency of 7.47%. By changing the wavelength of the seed laser, the output wavelength could be adjusted in the nanometer range. When the signal light passed through the methane gas pool at the distance of 10 m, the spectral intensity decreased obviously, and the feasibility of the signal light in the remote sensing of methane was preliminarily verified. Compared with direct detection by the seed light, the intensity of signal light is much higher, and it has great advantages in detection range and sensitivity.