基于2.8μm波段Er^(3+)∶ZBLAN激光光源的CO_(2)系统检测研究  

Research on CO_(2)System Detection Based on 2.8μm Band Er^(3+)∶ZBLAN Laser Source

作　　者：刘永岩 王坤阳 田颖 蔡恩林 LIU Yong-yan;WANG Kun-yang;TIAN Ying;CAI En-lin(Institute of Optoelectronic Materials and Devices,Hangzhou College of Optics and Electronic Technology,China Jiliang University,Hangzhou 310018,China;Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Shanghai 201800,China;Shanghai Advanced Research Institute,Chinese Academy of Sciences,Shanghai 201214,China;University of Chinese Academy of Sciences,Beijing 101408,China)

机构地区：[1]中国计量大学光学与电子科技学院,光电材料与器件研究院,浙江杭州310018 [2]中国科学院上海应用物理研究所,上海201800 [3]中国科学院上海高等研究院,上海201204 [4]中国科学院大学,北京101408

出　　处：《光谱学与光谱分析》2025年第4期1143-1149,共7页Spectroscopy and Spectral Analysis

基　　金：浙江省“高层次人才特殊支持计划”项目(2021R52032)资助。

摘　　要：基于中红外光源的吸收光谱技术是CO_(2)气体检测与分析的有效方法之一,在环境科学和医疗领域具有重要的应用潜力。但2.8μm波段CO_(2)的检测所使用的光源大都为商用的二极管激光器或半导体激光器,输出波长单一且光束质量较差,激光输出功率较小,在气体测试过程中易受环境波动的影响。本文构建了一种基于中红外光纤激光光源的CO_(2)气体检测系统,该系统以980nm半导体激光器为泵浦光源,采用1.9m的Er^(3+):ZBLAN光纤作增益介质,实现了2.8μm处高质量中红外激光输出,分析了该结构下光源的输出特性,当最大泵浦功率为6W时,激光输出光谱的中心波长为2783.09nm,谱宽为5.69nm,平均输出功率为1.21W,转换效率为20.3%,激光器在30min内输出功率波动小于4.5%,输出能量较为集中,拟合后的束腰半径Dx和Dy分别为0.035和0.038mm,光束质量因子Mx2和My2分别为1.096和1.224,输出光束质量与稳定性较好,大大降低了气体检测时环境波动的影响。在此基础上利用直接吸收光谱技术获得了CO_(2)通入前后的信号光谱,实验测得CO_(2)在2778.5~2784nm波段的吸收峰中心波长为2779.36、2780.70、2782.13和2783.55nm,与HITRAN标准库吸收峰中心波长差距小于0.05nm。根据LambertBeer定律反演得到的CO_(2)吸收谱线,在中心波长2780.7nm处吸收谱的峰值和半高宽值分别为5.33cm·mol^(-1)和0.18nm,同条件下HITRAN标准库对应的吸收谱峰值和半高宽值分别为5.38cm·mol^(-1)和0.12nm,差值仅为0.05cm·mol^(-1)和0.06nm,测试结果准确性较高,证明了该检测系统可用于CO_(2)气体检测领域。Absorption spectroscopy based on mid-infrared light sources is one of the effective methods for CO_(2)gas detection and analysis,and it has significant potential applications in environmental science and medical fields.However,most of the light sources used for the detection of CO_(2)in the 2.8μm band are commercial diode lasers or semiconductor lasers,which have a single output wavelength and poor beam quality,and the laser output power is small,which is susceptible to environmental fluctuations during the gas testing process.In this paper,a CO_(2)gas detection system based on a mid-infrared fiber laser light source is constructed,which uses a 980 nm semiconductor laser as the pump light source and 1.9 m Er^(3+)∶ZBLAN fiber as the gain medium to realize a high-quality mid-infrared laser output at 2.8μm.It analyzes the output characteristics of the light source under this structure.When the maximum pump power is 6 W,the center wavelength of the laser output spectrum is 2783.09 nm,the spectral width is 5.69 nm,the average output power is 1.21 W,and the conversion efficiency is 20.3%.The output power fluctuation of the laser is less than 4.5%within 30 min,and the output energy is relatively concentrated.The fitted beam waist radii D x and D y are 0.035 mm and 0.038 mm,and the beam quality factors M 2 x and M 2 y are 1.096 and 1.224,respectively.The better quality and stability of the laser's output beam dramatically reduces the effects of environmental fluctuations during gas detection.On this basis,the signal spectra before and after CO_(2)fluxing were obtained using direct absorption spectroscopy.The center wavelengths of the absorption peaks of CO_(2)in the 2778.5~2784 nm band were measured to be 2779.36,2780.70,2782.13,2783.55 nm,and the difference in the center wavelengths of the absorption peaks with the HITRAN standard library was less than 0.05 nm.The peak and half-height width of the CO_(2)absorption spectrum at the center wavelength of 2780.7 nm was 5.33 cm·mol^(-1)and 0.18 nm,obtained by inversion o

关 键 词：气体检测 中红外波段 2.8μm激光 二氧化碳 直接吸收 

分 类 号：TN21[电子电信—物理电子学]