基于超快光纤光源的脉冲内差频产生中红外激光的研究进展(特邀)  

Mid-Infrared Laser Generation by Intra-Pulse Difference Frequency Based on Ultrafast Fiber Light Source(Invited)

作　　者：陈晨[1] 罗万里 刘雪明 Chen Chen;Luo Wanli;Liu Xueming(School of Automation,Nanjing University of Information Science&Technology,Nanjing 210044,Jiangsu,China;School of Optoelectronic Engineering,Changchun University of Science and Technology,Changchun 130022,Jilin,China;School of Electronic Science&Engineering,Southeast University,Nanjing 210096,Jiangsu,China)

机构地区：[1]南京信息工程大学自动化学院,江苏南京210044 [2]长春理工大学光电工程学院,吉林长春130022 [3]东南大学电子科学与工程学院,江苏南京210096

出　　处：《光学学报》2024年第17期214-233,共20页Acta Optica Sinica

基　　金：国家自然科学基金(62035010,61525505)。

摘　　要：超快中红外(MIR)激光处于大气透射窗口和人眼安全波段范围内,在环境监测、光电对抗、激光雷达和外科手术等领域有着重要作用。目前主要由晶体的非线性频率变化来产生宽带宽、长波长以及窄脉冲宽度的超快MIR激光。其中,基于短波长的超快光纤激光源的脉冲内差频产生(IP-DFG)技术是一种非常简便的非线性频率变换方法。本文阐述了MIR激光的产生、IP-DFG技术的基本原理和研究进展以及超快MIR激光的应用,并且对IP-DFG系统未来的发展与应用前景进行展望。Significance The spectral band of 2-20μm is defined as the mid-infrared(MIR)band,which is within the atmospheric transmission window and eye-safe range and plays an important role in environmental monitoring,optoelectronic countermeasures,lidar,and surgical operations.For example,MIR band lasers cover the absorption bands of many gas molecules,such as H_(2)O,CO_(2),NH3,and O3,which can be employed in environmental monitoring and differential absorption lidars.Additionally,due to the large absorption coefficient and shallow penetration depth of 2-20μm lasers in biological tissues,they are widely adopted in laser medical surgery.Currently,there are two major methods for generating MIR ultrafast lasers.The first is to directly generate MIR lasers based on the energy level structure of the gain medium itself,such as solid lasers,gas lasers,fiber lasers,and quantum cascade lasers(QCLs).The other is to adopt nonlinear frequency conversion technology to generate MIR ultrafast lasers,such as supercontinuum light generation,optical parametric processes,difference frequency,and four-wave mixing.QCLs are a new type of semiconductor laser,which enables semiconductor lasers to operate in the MIR band.The working principles of traditional semiconductor lasers and QCLs are shown in Fig.1.QCLs are characterized by compact structure,easy wavelength tuning,and long lifetime.However,their manufacturing process is complex and expensive,and features high environmental requirements and poor beam quality,thus limiting its application range.Its application is limited to long-distance remote sensing detection and optoelectronic countermeasures.The core technology of mid-infrared solid-state lasers is to employ laser crystals as gain media,to dope impurities in the crystals to change their energy level structure,and finally to achieve light amplification via the cavity to produce MIR laser output.Among them,the main doped impurities are rare earth ions(Tm^(3+),Ho^(3+),Er^(3+))and transition metals(Cr^(2+),Fe^(2+)).As shown in Fig.2,it s

关 键 词：超快光学 中红外激光 非线性频率变换 脉冲内差频产生技术 

分 类 号：TN24[电子电信—物理电子学]