GSA和ESA双波长泵浦2.3μm波段Tm:YAP激光器  

GSA and ESA Dual-Wavelength Pumped 2.3 μm Tm:YAP Lasers

作　　者：王飞 黄海涛 鲍玉朔 李子涵 沈德元 Wang Fei;Huang Haitao;Bao Yushuo;Li Zihan;Shen Deyuan(School of Physics and Electronic Engineering,Jiangsu Normal University,Xuzhou,Jiangsu 221116,China)

机构地区：[1]江苏师范大学物理与电子工程学院,江苏徐州221116

出　　处：《中国激光》2022年第1期232-239,共8页Chinese Journal of Lasers

基　　金：国家自然科学基金(61875077)。

摘　　要：Tm^(3+)离子^(3)F_(4)能级的粒子数捕获效应是影响2.3μm掺铥激光器高效运转的重要因素。报道了基态吸收(GSA,^(3)H_(6)→^(3)H_(4))和激发态吸收(ESA,^(3)F_(4)→^(3)H_(4))双波长泵浦2.3μm波段Tm∶YAP激光器。使用785 nm(GSA)和1470 nm(ESA)双波长泵浦方案能够精准减少^(3)F_(4)能级的粒子数,有效增加^(3)H_(4)能级粒子数布居。在双波长泵浦沿a轴切割的Tm∶YAP晶体中,使用透过率T=1.5%的输出镜,2274 nm和2383 nm双波长激光最大输出功率为2.28 W,相比于单波长泵浦方案提高了65.2%。使用T=2.8%输出镜,2383 nm激光的最大输出功率为942 mW,较单波长泵浦方案提高了84.3%。通过采用特殊镀膜的输出镜,进一步实现了2446 nm激光运转,最大输出功率为1.62 W,较单波长泵浦下的激光输出功率提高了48.6%。实验结果表明,GSA和ESA双波长泵浦方案为实现2.3μm掺铥激光器获得更高的输出功率提供了一种有效技术手段。Objective Midinfrared lasers emitting in the 2-3μm range are a popular research topic in laser science and applications.Presently,the majority Tm-doped laser research is focused on the^(3)F_(4)→^(3)H_(6) transition,with the laser wavelength ranging from 1.8to 2.1μm.Tm^(3+) ions have multiple potential laser transition processes owing to their rich energy level structure.Exploring the potential laser transition process of activating ions outside of the conventional waveband is an important step toward directly obtaining a new midinfrared wavelength.The^(3)H_(4)→^(3)H_(5) transition in Tm^(3+) ions at 2.3μm has attracted considerable attention lately.The following are the advantages of achieving a 2.3μm laser operation in a Tm-doped laser medium.Tm^(3+) ions absorb strongly at~800nm,which is the emission wavelength of commercial AlGaAs laser diodes(LDs).Then,a low-cost LD-pumped all-solid-state2.3μm Tm-doped laser can be designed.Furthermore,the^(3)H_(4)→^(3)H_(5)transition is a four-level structure that can support room temperature laser operation with a negligible reabsorption effect.The 2.3μm region is in the weak absorption zone of water,and the laser operation is less affected by the surrounding air humidity.Compared with the scheme of using Cr^(3+)-doped II-IV media to realize 2.3μm laser,the preparation of Tm-doped laser materials is more mature and reliable,and the types of the matrix are more abundant(such as Tm:YAG,Tm:YAP,Tm:YLF),which provides more possibilities for finding Tm-doped laser materials with excellent spectral characteristics,high thermal conductivity,high optical transmittance,and stable physicochemical properties.However,the population trapping effect of the^(3)F_(4)level limits the power scaling of a 2.3μm Tm-doped laser on the transition of^(3)H_(4)→^(3)H_(5).On one hand,Tm^(3+)ions(^(3)H_(4)+^(3)H_(6)→^(3)F_(4)+^(3)F_(4))have a strong cross-relaxation process.On the other hand,the long lifetime of^(3)F_(4)level will result in a large accumulation of Tm^(3+)ions at the^(

关 键 词：激光器 2.3μm掺铥激光器 基态吸收 激发态吸收 双波长泵浦 Tm∶YAP 

分 类 号：TN248.1[电子电信—物理电子学]