高光束质量、窄线宽皮秒脉冲KTiOAsO_(4)光参量振荡器的研究  

High-Beam-Quality and Narrow-Linewidth Picosecond Optical Parametric Oscillator Based on KTiOAsO_(4)

作　　者：焦夏卓 买里克古丽·艾合买提 周玉霞 苏比努尔·牙库甫 冶建强 杨曦凝 Jiao Xiazhuo;Mailikeguli Aihemaiti;Zhou Yuxia;Subinuer Yakufu;Ye Jianqiang;Yang Xining(Xinjiang Key Laboratory for Luminescence Minerals and Optical Functional Materials,College of Physics and Electronic Engineering,Xinjiang Normal University,Urumqi 830054,Xinjiang,China;College of Chemistry and Chemical Engineering,Xinjiang Normal University,Urumqi 830054,Xinjiang,China)

机构地区：[1]新疆师范大学物理与电子工程学院,新疆发光矿物与光功能材料研究重点实验室,新疆乌鲁木齐830054 [2]新疆师范大学化学化工学院,新疆乌鲁木齐830054

出　　处：《中国激光》2025年第2期226-232,共7页Chinese Journal of Lasers

基　　金：新疆维吾尔自治区自然科学基金(2022D01A221);新疆维吾尔自治区人才发展基金“天池英才”引进计划青年博士项目;教育部产学合作协同育人项目(231104090093007)。

摘　　要：基于同步泵浦技术和砷酸钛氧钾(KTiOAsO_(4))晶体,研究了由1μm全固体皮秒脉冲激光泵浦的高功率、高光束质量、高功率稳定性和窄线宽的信号光单谐振光参量振荡器。通过理论模拟腔参数、对比腔型结构、压缩腔镜折叠角,搭建了一种稳定、高效、可灵活调节的五镜Z字形折叠腔,实现了近-中红外波段皮秒脉冲激光输出。当泵浦功率为18.5 W时,分别获得了3.55 W的近红外信号光(1535 nm)和1.75 W的中红外闲频光(3468 nm),其对应的转换效率分别为27.8%和13.6%,光束质量因子分别约为1.12和1.17,光谱半峰全宽分别为0.27 nm(1.15 cm^(-1))和0.75 nm(0.62 cm^(-1)),在6 h内的功率稳定性分别为1.6%(均方根,RMS)和1.5%(RMS),这说明在近-中红外波段获得了高光束质量、高功率稳定性和窄线宽的超快脉冲激光输出。Objective The 1.5μm waveband laser has attracted remarkable attention in various fields,including radar,remote sensing,laser vibration measurement,and material microprocessing,because of its low atmospheric-transmission loss and safety for human eyes.The 3‒5μm waveband laser has a typical“atmospheric infrared window”and fingerprint band,and it can be used for molecularcontent detection,environmental detection,imaging,telemetry,and biomedicine.Owing to its high spectral purity,long coherence length,and low phase noise,a narrow-linewidth,high-beam-quality infrared laser can be better applied in gravitational-wave detection,cold atomic physics,coherent optical communication,and optical-precision detection.An optical parametric oscillator(OPO)is an effective device for frequency conversion and can directly convert the wavelength of a solid-state laser into near-and midinfrared wavelengths.Compared to the femtosecond OPO,the picosecond OPO not only has a high average power output but also exhibits a good balance between the pulse width and narrow spectral bandwidth.Methods A schematic of the synchronous-pumping picosecond KTiOAsO_(4)(KTA)-OPO,used for high-power,high-beam-quality,narrow-bandwidth laser generation in the near-and mid-infrared wavelengths,is presented in Figure 1.The pump source is an allsolid-state picosecond laser based on a diode-pumped Nd∶YVO_(4)crystal,which provides up to 18.5 W of maximum output power at 1064 nm in 15 ps pulses at a 120 MHz repetition frequency.A half-wave plate was used to rotate the polarization of the pump beam to excellently match the phase in the KTA crystal.Using a plano-concave lens with a focal length of 100 mm,the output of the pump beam was focused to~63 mm at the center of the nonlinear crystal.The cavity parameters and spacing were theoretically estimated using LASCAD software.To achieve the best mode coupling of the pump and signal beams in the nonlinear crystal,the signal beam had a spot radius of 64μm at the center of the KTA.The 90°-cut KTA crystal(5 m

关 键 词：非线性光学 超快脉冲 光参量振荡器 KTiOAsO_(4) 高光束质量 

分 类 号：O437[机械工程—光学工程]