基于双波长激光器的集成化中红外双光梳系统(特邀)  

Integrated Mid-infrared Dual-comb System Based on a Dual-wavelength Laser(Invited)

作　　者：杨梅 闻齐 刘婷婷 闫明 曾和平[1,2,3] YANG Mei;WEN Qi;LIU Tingting;YAN Ming;ZENG Heping(State Key Laboratory of Precision Spectroscopy,East China Normal University,Shanghai 200062,China;Chongqing Key Laboratory of Precision Optics,Chongqing Institute of East China Normal University,Chongqing 401121,China;Jinan Institute of Quantum Technology,Jinan 250101,China)

机构地区：[1]华东师范大学精密光谱科学与技术国家重点实验室,上海200062 [2]华东师范大学重庆研究院精密光学重庆市重点实验室,重庆401121 [3]济南量子技术研究院,济南250101

出　　处：《光子学报》2023年第3期110-118,共9页Acta Photonica Sinica

基　　金：国家自然科学基金(No.62035005);上海市市级科技重大专项(No.2019SHZDZX01-ZX05);重庆市自然科学基金(No.2022NSCQ-JQX1103)。

摘　　要：中红外双光梳光谱检测系统因其高分辨、高灵敏、快速测量的特性为极低浓度气体的标定带来了革新技术。本文用单腔双波长激光器输出的异步双波长脉冲替代两台锁模激光器,结合非线性差频技术,发展了集成实用化的中红外双光梳系统。共腔产生的1034 nm与1039 nm双波长脉冲序列,其重复频率差约为1.18 kHz,且因共模噪声被抑制,脉冲间的相对稳定性较高。利用级联放大器将种子脉冲光功率提升至1.1 W后,与2 W的1549.315 nm的连续激光非线性差频,将激光器输出波段拓展至中红外。产生的中红外激光功率可达3.5 mW,光谱覆盖范围超过50 nm。对中红外双光梳的相干性进行测量,与1μm的底层双光梳相比,中红外双光梳拍频梳齿频率间隔、信噪比、线宽等无明显劣化,可为复杂环境下的痕量分析提供可行方案。The mid-infrared dual-comb spectroscopy has innovated the detection of trace gases due to its high resolution,high sensitivity,and short response time.The traditional dual-comb system based on mode-locked lasers,electro-optic modulation or nonlinear optical micro-resonators is always combined with shortcomings of complex structure,high cost,few comb teeth,and poor practicability.In recent years,dual-wavelength mode-locked lasers that allow two asynchronous pulse trains to oscillate simultaneously have attracted increasing attention owing to their great potential in facilitating robust and precise dual-comb spectroscopy.In this paper,with two collimators and a segment of polarizationmaintaining fiber acting as a Lyot filter,two asynchronous pulse trains centered at 1034 nm and 1039 nm respectively can emit from a single-cavity dual-wavelength laser,which is based on a Nonlinear Amplifying Loop Mirror structure.The repetition rate difference between the dual-wavelength pulses is about 1.18 kHz and the 3 dB spectral width per wavelength is~1.6 nm.The mutual coherence is maintained owing to a shared laser cavity,and common-mode noise is canceled.The radio frequencies of the dual-wavelength pulses are traced and~60 Hz frequency drift of each wavelength is measured within 10 hours yet only a 3.5 Hz frequency shift and 0.45 Hz standard deviation of the repetition rate difference is observed.The difference in magnitude indicates the high coherence and great environmental stability of the dual-wavelength pulses.To demonstrate the coherence between the dual-wavelength pulses,the multiheterodyne beat notes are detected.Because of the optical spectral overlap,the mode-resolved beat notes with a frequency interval of 1.18 kHz and~25 dB signal-to-noise ratio are observed.Limited by the resolution bandwidth of the spectrum analyzer,the obtained full width at half maximum of each beat note is about 12 Hz.The average power of the seed pulses is scaled up to 1.1 W with a cascade amplifier to avoid excessive spontaneous emission no

关 键 词：光纤激光器 光学频率梳 双光梳光谱技术 中红外 双波长锁模 

分 类 号：TN247[电子电信—物理电子学]