22 W,240 fs高功率中红外飞秒光学频率梳  

22⁃W,240⁃fs High⁃Power Mid⁃Infrared Femtosecond Optical Frequency Comb

作　　者：蔡宇 田昊晨 曹士英[2,3] 秦冠仕 胡明列[1] Cai Yu;Tian Haochen;Cao Shiying;Qin Guanshi;Hu Minglie(Ultrafast Laser Laboratory&Key Laboratory of Optoelectronic Information Technology(Ministry of Education),School of Precision Instrument and Opto-electronics Engineering,Tianjin University,Tianjin 300072,China;Division of Time and Frequency Metrology,National Institute of Metrology,Beijing 100029,China;Key Laboratory of State Administration for Market Regulation(Time Frequency and Gravity Primary Standard),Beijing 100029,China;State Key Laboratory of Integrated Optoelectronics,College of Electronic Science and Engineering,Jilin University,Changchun 130012,Jilin,China)

机构地区：[1]天津大学精密仪器与光电子工程学院超快激光研究室&光电信息技术教育部重点实验室,天津300072 [2]中国计量科学研究院时间频率计量研究所,北京100029 [3]国家市场监管重点实验室(时间频率与重力计量基准),北京100029 [4]吉林大学电子科学与工程学院集成光电子学国家重点实验室,吉林长春130012

出　　处：《中国激光》2024年第5期128-134,共7页Chinese Journal of Lasers

基　　金：国家自然科学基金(61827821);国家自然科学基金青年科学基金(62105237)。

摘　　要：中红外飞秒光学频率梳在天文学、药物检测、生物化学、大气检测和材料科学等领域中有着广阔的应用前景。报道了一个高功率中红外飞秒光学频率梳系统,该系统主要由掺铒光纤飞秒光学频率梳、超连续谱产生装置、双包层掺铥光纤放大器和基于透射式衍射光栅对的压缩器四部分构成。掺铒光纤光学频率梳输出平均功率为350 mW、中心波长为1565 nm、重复频率为198 MHz、脉冲宽度为55 fs的飞秒激光,并将其注入到一段正色散高非线性光纤中,产生1100~2200 nm超连续光谱。超连续光通过由掺铥光纤构成的自泵浦放大器,产生中心波长为1925 nm、平均功率为50 mW的飞秒脉冲。将此脉冲作为双包层掺铥光纤放大器的种子源,功率被放大到36.07 W,压缩后得到平均功率为22.72 W、脉冲宽度为240 fs的飞秒激光脉冲输出。Objective The femtosecond optical frequency comb(FOFC)comprises a series of ultra-short laser pulses with the same temporal separation in the time domain and discrete,equidistant,and stable phase-related frequency components in the frequency domain.The FOFC can accurately measure the absolute frequency of an atomic clock and serve as a natural time-frequency reference.Currently,the most stable and compact light source is the mode-locked erbium-doped fiber laser with a central wavelength of 1.55μm,typically employing highly nonlinear fibers to broaden the spectrum across the entire transparent range of silica fiber(350-2400 nm).However,the output power of the erbium-doped fiber FOFC is generally in the range of a few hundred milliwatts.Therefore,increasing the output power of the FOFC remains a crucial challenge.The mid-infrared FOFC holds significant application value in next-generation spectroscopy,as it can be used to detect gases such as carbon dioxide and ammonia and extend the FOFC wavelength to the molecular fingerprint spectrum range(3-20μm)through nonlinear crystals.This spectrum range is vital for chemical composition analysis,making the development of high-power mid-infrared FOFCs a pressing need.Methods This system comprises an erbium-doped fiber FOFC,a super-continuum converter,a double-cladding thulium-doped fiber amplifier system,and a transmission diffraction grating pulse compressor.Initially,the erbium-doped fiber FOFC utilizes a highly nonlinear fiber with normal dispersion for frequency broadening.Additionally,a self-pump amplifier composed of thuliumdoped fiber generates a femtosecond seed with a central wavelength of 1925 nm.This seed is injected into a chirped pulse amplification system comprising a 55 m long highly nonlinear fiber with normal dispersion,a three-stage thulium-doped fiber amplifier,and a transmission diffraction grating pulse compressor.To characterize the noise of the high-power mid-infrared FOFC,we analyze the relative intensity noise and the phase noise of the pulse trai

关 键 词：非线性光学 光学频率梳 飞秒激光 啁啾脉冲放大 中红外波段 

分 类 号：TN248[电子电信—物理电子学]