基于平坦相干超连续谱的近红外光梳光谱技术  

Near-Infrared Comb Spectroscopy Technology Based on Flat Coherent Supercontinuum

作　　者：张静 蔡玉汝[1,2] 黄勤清 周文 程林 Zhang Jing;Cai Yuru;Huang Qinqing;Zhou Wen;Cheng Lin(NARI Group Corporation(State Grid Electric Power Research Institute),Nanjing,Jiangsu 21100Q,China;Wuhan NARI Co Ltd.,State Grid Electric Power Research Institute,Wuhan,Hubei A30074,China)

机构地区：[1]南瑞集团有限公司(国网电力科学研究院),江苏南京211006 [2]国网电力科学研究院武汉南瑞有限责任公司,湖北武汉430074

出　　处：《中国激光》2021年第7期207-213,共7页Chinese Journal of Lasers

基　　金：国网电力科学研究院有限公司(524625180044)。

摘　　要：研究了相干度高且光谱平坦的近红外超连续谱(SC)光梳的产生以及超宽带光梳光谱的测量问题。利用掺铒光纤光梳脉冲抽运高非线性色散位移光纤,获得光谱覆盖范围为1250~1900 nm的平坦SC,并通过理论模拟和实验验证了SC的高相干性。同时,在该SC光梳源的基础上,利用傅里叶变换光谱技术,对包含HF、^(12)C_(2)H_(2)、^(12)CO、H_(2)O的混合气体样品进行超宽带高分辨分子光谱测量。实验得到的数据与HITRAN2012数据库模拟的结果一致,误差小于1.6%,验证了基于平坦SC光梳光谱测量多组分气体的可行性。Objective Optical frequency comb(OFC)is a coherent light source with excellent time-frequency stability.In frequency domain,an OFC is a set of frequency comb teeth with narrow linewidth and equidistant distribution.Because of this characteristic,the OFC has revolutionized the approach to molecular spectroscopy,making it possible to simultaneously and rapidly measure hundreds of molecular spectral lines with high resolution.The OFC spectroscopy technology has become a hot spot in the field of spectral technology,and has promoted the technological changes in the fields of optical coherence tomography,trace analysis and optical remote sensing.However,due to the limitation of the light source gain bandwidth,the comb spectrum is still unable to compare with the traditional Fourier transform spectroscopy technology in ultra-wideband spectrum measurement,which limits its applications in,such as chemical analysis and atmospheric environment monitoring.At present,supercontinuum(SC)generation technology is the main way to expand the spectral width of light sources.However,the strong nonlinear effect and phase modulation instability inside nonlinear fibers will not only cause strong amplitude oscillation and jitter of SC spectrum,but also introduce additional phase(frequency)noise,resulting in obvious decoherence.These problems seriously limit the application of SC generation technology in comb and spectrum measurement.Here,the generation of near infrared SC comb with high coherence and flat spectrum is investigated.The coherence is confirmed by beat note measurements and nonlinear Schrodinger equation(NLSE)based numerical simulation.The source could be useful for broadband gas sensing in monitoring of electrical installations.Methods First,an erbium-doped fiber comb is harnessed for producing a flat SC with spectral coverage of 1250--1900 nm in a high nonlinear dispersion shifted fiber(HNL-DSF).A home-made nonlinear-polarization-rotation(NPR)mode-locked fiber laser comb delivered a train of 650 fs pulses at a repetition ra

关 键 词：非线性光学 超连续谱 相干特性 光纤光学 

分 类 号：O436[机械工程—光学工程]