单、双纵模腔式光泵远红外激光器的实验研究

实验上采用可选纵模的TEA－CO2激光器作泵浦源,用CO2－9R（16）线泵浦小型腔式NHG3远红外激光器,在单、双纵模泵浦条件下均获得波长为90．4μm的远红外谱线。对单、双纵模腔式光泵远红外激光的输出特性和工作气压作了实验比较研究,发现双纵模腔式光泵远红外激光可获得更强的远红外输出,具有较低的最佳工作气压值,并可在较宽的气压范围内工作。     

缓冲气体对光抽运远红外激光器频谱特性的影响

基于分子振动弛豫理论完善了缓冲气体的作用模型，利用半经典密度矩阵理论与量子力学理论，定量分析研究了缓冲气体对小型光抽运远红外激光过程的作用机理以及缓冲气体作用下小型腔式光抽运NH3分子远红外激光器的频谱特性，讨论了工作气压、抽运功率等工作参数对频谱特性的影响，并对理论计算结果进行了实验验证．二者符合得较好。研究结果表明，在小型光抽运远红外激光器中加入适当的缓冲气体，大量工作气体分子与缓冲气体分子之间的无规碰撞会引起谱线加宽，而且可以使远红外激光输出信号增强。     

双模光泵反射腔式THz激光中的多拉曼效应

在半经典密度矩阵理论的基础上,理论研究了双纵横CO2-9R（30）光泵小型腔式NH3分子67.2μm THz激光过程中的多拉曼相互作用,并研究了不同泵浦功率,工作气压和激光管长等工作参数条件下多拉曼相互作用规律和对67.2μm远红外激光频谱特性的影响。     

一体化的小型腔式光泵NH3分子远红外激光器

研制了包括泵浦源在内的一体化小型腔式光泵ＮＨ３远红外激光器，实验测量了输出功率、工作气体压强、腔体长度与腔体耦合条件之间的优化规律：发现了小型腔式光泵远红外激光器中普遍存在的特别宽带的激光辐射现象，这将是解决远红外激光频率大范围连续可调谐的一个新途径。     

栅网耦合的光泵腔式亚毫米波激光器及最佳工作气压研究

采用电感性金属网栅作为光学谐振腔的反射镜和输入输出耦合器 ,设计制作了长度分别为 10 0cm、2 0 cm和 10 cm的 Fabry- Perot腔式亚毫米波激光器。运用半经典密度矩阵理论 ,通过迭代法计算了光泵腔式 NH3分子亚毫米波激光器的最佳工作气压。在实验上测量了 TEA CO2 - 10 R(8)和 9R(16 )泵浦上述 NH3分子亚毫米波激光器的最佳工作气压。理论计算与实验结果一致。     

栅网耦合的光泵腔式亚毫米波激光器的工作参数优化

采用半经典密度矩阵理论并运用迭代法对小型光泵腔式NH3分子亚毫米波激光器的工作气压、输入输出网栅的功率反射系数等工作参数优化问题进行了深入的理论研究;同时,进行了相关的实验研究,实验结果与理论计算符合得较好。     

小型光系NH_3分子气体远红外激光实验

本文详细介绍最有希望的远红外信号源—光泵远红外激光器（ＯＰＦＩＲＬ）实验系统，并改进了以往的检测方法，同时对ＮＨ_３分子２９２×１０（－６）米的超辐射激光谱线进行了实验研究。     

小型脉冲冲光泵NH3分子远红外激光的Raman频谱研究

通过求解量子系统的密度矩阵方程,采用迭代了计算在TEACO2－10R（6）泵浦下,小型脉冲光泵NH3分子远红外激光器中,NH3分子的V2：a→sR(0,0)跃迁和a→sQ(5,4)跃迁的频谱特性。理论计算结果表明,对于a→sR(0,0)跃迁,当工作气压比临界值Pc高或泵功率密度比临界值Ipoc低时,将出现Raman频谱尖峰;对于a→sQ(5,4)跃迁,不出现频谱尖峰,频谱尖峰现象的根源是AC Stark分裂的双光子相互作用的结果。     

金属网栅耦合的光泵腔式亚毫米波激光器

采用电感性金属网栅作为光学谐振腔的反射镜和反射镜和输入输出耦合器，设计制作 了长度分别为１００ｃｍ、２０ｃｍ和１０ｃｍ的Ｆａｂｒｙ－Ｐｅｒｏｔ腔式亚毫米波激光器，分别用ＴＥＡ－ＣＯ２激光器的１０Ｒ（８）线和９Ｒ（１６）线洋浦源，成功地获得光泵ＮＨ３分子亚毫米波激光，根据Ｆ－Ｐ腔的多光束干涉特性，动用量子系统的密度四理论，对上述激光器光学特性和ＮＨ３分子亚毫米波激光的频谱特性进行了理论研究。     

新颖激光器的物理机制

论述了电激励远红外激光器、光泵远红外激光器和自由电子激光器产生远红外受激发射的物理机制。以氰化氢激光器和甲基氟激光器为例,分析了HCN分子和CH_3F分子产生受激发射的物理过程和受激发射特性。用三能级二光场的密度矩阵方程     

Operating Parameter Comparison of Pulsed Optically Pumped NH3 and CH3OH F-P Cavity Far-Infrared Laser

Based on the density matrix theory of quantum system, the optimum operating parameters of pulsed optically pumped NH3 and CH3OH F-P cavity far-infrared laser (NH3/CH3OH-OPFIRL) were studied and compared theoretically. The differences of the operating parameters between the NH3-OPFIRL and CH3OH-OPFIRL were found and discussed. Experimentally, the curves of output power verses gas pressure in NH3 and CH3OH F-P cavity lasers pumped by TEA-CO2 laser were measured, and the optimum operating gas pressure were obtained. The experimental results were in agreement with theoretical calculations.     

Experimental Study of Pulsed Optically Pumped Superradiant and Cavity NH3 Far-Infrared Laser

Using a grating tuned TEA-CO2 laser with 10R(8) and 9R(16) line to pumped superradiant NH3 far-infrared (FIR) laser which operated in the mode of amplified stimulated emission and Fabry-Perot cavity NH3 FIR laser with a sample tube of 100cm and 20cm in length respectively, the corresponding pulsed FIR lasers were obtained successfully. Meantime, the experimental measure method was improved. Besides, the operating performance and the spectral characteristics of superradiant and cavity NH3-OPFIRL were studied experimentally.     

Study on spectral characteristics and operating parameters ofoptically pumped NH3 FIR cavity laser

By solving the density matrix equations of a quantum system and taking into account the multibeam interference characteristics of a Fabry-Perot cavity, the output power density of an optically pumped NH ₃ far-infrared (FIR) cavity laser was calculated by means of the iteration method. Based on the calculations, the spectral characteristics and operating parameters of the laser were studied. Experimentally, by using inductive metallic meshes as reflectors and couplers, a series of FIR cavity lasers with a sample tube of 10, 20, and 100 cm in length were designed and constructed, and the emissions of the NH₃ cavity lasers pumped by a TEA-CO₂ laser with a 10R(8) or 9R(16) line were measured. The experimental results were in good agreement with theoretical calculations     

Spectral Characteristics Comparison of Pulsed Optically Pumped NH3 and CH3OH Far-Infrared Laser

By solving the density matrix equations of a quantum system, the output power intensity of pulsed optically pumped NH3 and CH3OH far-infrared laser (OPFIRL) was calculated respectively by means of iteration method. Based on the calculations, the spectral characteristics of pulsed NH3-OPFIRL and CH3OH-OPFIRL were studied and compared theoretically. The differences of spectral characteristics between the NH3-OPFIRL and CH3OH-OPFIRL were found. Experimentally, a series of FIR emissions of NH3 and CH3OH cavity lasers pumped by TEA-CO2 laser were measured, and the experimental results were in agreement with theoretical calculations.     

Effects of Buffer Gas on the Output of Optically Pumped NH3 Far-Infrared Cavity Laser

By solving the semi-classical density matrix equations and developing a buffer gas mechanism model, the effects of buffer gas on the output power of optically pumped NH₃ far-infrared cavity laser were calculated and verified by experiment. Our results showed that: the output power of NH₃ far-infrared laser could be increased when certain buffer gas was added into the laser medium, and there existed an optimum ratio of gases mixture and an optimum operating gas pressure which could make the output power of far-infrared laser reach maximum.     

Spectral Characteristics of Miniature Two-Longitudinal-Mode Optically Pumped FIR Laser

With the assumption that the pump source was two-longitudinal-mode, the semiclassical density matrix equation of a three-energy-level system was solved. By means of iteration method, the spectral characteristics of miniature two-longitudinal-mode optically pumped NH₃ far-infrared cavity laser, which was pumped by CO₂-9R(16) line, were calculated numerically. The influences of operating parameters on laser spectrum were studied intensively.     

Theoretical study of miniature optically pumped cavity NH3 Far-infrared laser

Miniature optically pumped cavity NH3 Far-infrared laser was studied theoretically, with the length of the FIRL cavity as short as 1.5cm, the dependences of FIRL output power and laser lineshape on operating gas pressure and output coupling condition, and on the effect of laser line saturation broadening were calculated.     

Study on Stark Effect in Optically Pumped Far-Infrared Laser

The output intensity of optically pumped NH3 molecules far-infrared laser (NH3-OPFIRL) was calculated by solving the density matrix equation and by means of iteration method. Meanwhile, the spectral characteristic of AC Stark splitting was studied. Finally, the F-P interferogram of NH3-OPFIRL pumped by CO2-10R(8) line was measured. The experimental results were in good agreement with the theoretical calculation results.     

Spectra of optically pumped superradiant and cavity NH3 far-infrared laser

Based on the density matrix theory of quantum system, the spectra of optically pumped superradiant and cavity NH₃ far-infrared (FIR) lasers were calculated by means of iteration method. The calculation showed that, compared with the optically pumped superradiant FIR laser, the cavity laser had a wider band spectrum of FIR emission and a higher output power under certain condition, moreover, the spectra of cavity laser had multi longitudinal-mode structure.