钾原子中由四波,六波混频过程产生的相干辐射

当双光子共振激发钾原子于６Ｓ能级时，由光泵受激辐射，串级受激辐射参与的四波、六波混频以及电离复合的布居过程，产生了位于可见区的诸多相干辐射，文中对混频机制进行了分析和讨论，并对所测得的相干辐射进行了标识。     

由双光子共振激发钾蒸气产生红外受激辐射以及紫外和可见相干辐射

当双光子共振激发钾原子到7S能级时,测得了一系列位于红外区的光泵受激辐射和串级受激辐射.由光泵受激辐射与泵浦光的双光子共振四波混频过程,产生了对应于6P-4S和5P-4S的强相干辐射.而这两个相干辐射又具有泵浦光的作用,通过接联的四波混频过程产生位于紫外和可见区的许多相干辐射.文中对测到的红外受激辐射以及紫外和可见相干辐射的产生过程进行了讨论.     

钾原子中多种受激辐射参与的混频过程

当双原子共振激发钾原子于６Ｓ能级时,由光泵受激辐射和电离复合受激辐射参与的六波或四波混频,产生了位于紫外和紫区的诸多相干辐射、文中对多种混频机制进行了分析和讨论,并对所测得的相干辐射线进行了标识．     

双光子共振激发钠原子六波混频过程

双光子激发钠原子所产生的级联受激辐射光子与入射激光双光子可产生光波混频。实验共观测到十一条六波混频与十条四波混频谱线。理论分析表明脉冲激光泵浦下的光波混频过程仍可用稳态近似计算混频光强。非线性极化系数X不仅与基态布居数也与激发态布居数有关。X的共振增强效应对获得强混频输出有重要作用。     

Na原子中3S—4D双光子共振增强紫外相干辐射的观测和研究

用Na原子3S—4D双光子共振增强的受激超Raman散射、四波混频和光泵受激发射过程,获得230—340nm范围内两组紫外相干辐射,分析了这一系列紫外相干辐射的产生机制和谐线特性。     

由混合激发钠分子—原子系统产生的强度振荡变化的红外受激喇曼散射

本文报道以等频二步激发钠分子-原子系统,观测到强度随泵浦光的调谐而呈振荡变化的3P—4P受激喇曼散射,以及对应4D—4P和4F—3D跃迁的红外受激辐射和由四波混频产生的816.8～822.1nm区内可调谐相干辐射。文中对这些过程进行了分析讨论。     

钾蒸气中的偶极禁戒双光子共振四波混频和混合激发能量转移受激辐射

本文首次报道了由钾分子-原子系统的混合激发和碰撞能量转移过程产生4F→3D受激辐射以及由钾原子的4S→4F偶极禁戒双光子共振产生4F→3D受激辐射和四波混频的研究结果。     

基于半导体光放大器四波混频原理的光采样

建立了可研究强超短光脉冲放大特性且包含自由载流子吸收、受激辐射、双光子吸收、光谱烧孔和超快非线性折射效应的半导体光放大器理论模型,用以建立脉冲四波混频模型,并进一步仿真了基于半导体光放大器的光采样过程,重点讨论了自由载流子吸收、双光子吸收效应对采样特性的影响。仿真结果与实验结果相符。     

汞蒸汽中双光子共振四波和频产生125nm的相干辐射

利用汞原子6~1S_0—7~1S_0双光子共振四波和频产生了125nm的相干辐射.对双光子共振增强效应、双光子共振克尔(Kerr)效应进行了研究.讨论了平面波和聚焦情况下最佳相位匹配的条件.实验中还观测到了四波参量振荡和四波差频的信号输出.     

锂分子2~3π_g-a~3∑_u~+受激扩散带辐射线型的理论计算

本文利用由RKR方法计算得到的锂分子2~3∏_g态和a~3∑_u~+态(束缚部分)的势能曲线求解振动薛定谔方程,获得了2~3∏_9—a~3∑_u~+跃迁的F-C因子,自发辐射系数,进而计算了该跃迁的荧光强度和受激辐射带强度的光谱分布,其结果与实验测得的由双光子激发锂分子产生的受激扩散带辐射相吻合.     

UV and IR coherent radiation generated simultaneously by two-photon and hybrid excitations in sodium vapor

UV coherent radiation at 330.2 nm and IR stimulated radiations at 2.34μm,2.21μm and 1.64μm were generated via processes of unequal-frequency two-photon(3S-6S)resonantly enhanced excitation and equal frequency hybrid resonant excitation with particularexcited wavelength in Na_2-Na system.The competition of the two processes is obviously.     

由宽波段多光子作用产生的锂分子高位态受激辐射

本文报道了以６２０．６￣６６５．０ｎｍ范围内任意波长激光作用下产生的锂分子高位态紫外扩散带受激辐射的实验结果,在锂分子－原子系统中,由激光双光子激发、并通过碰撞能量转移过程以及多光子电离复合过程使锂分子高位态获得布居,从而得到紫外区扩散受激辐射,该辐射来自较高的某个三重态向低排斥态ａ＾３Σｕ＾＋的跃迁的结果。文中对有关的辐射特性及激发机制进行了详细的分析和讨论。     

Two-photon excited parametric emission from sodium atoms

Tunable coherent radiation around 840, 830, and 795 nm has been generated upon two-photon excitation of sodium 4d and 5s levels, respectively. The generation is due to special parametric processes. A molecular nature of the emissions, as recently proposed, can be ruled out by the performed investigations.     

钾蒸汽中双光子激发产生2~3∏_g—α~3∑_u~+扩散带受激辐射

本文报道了在K_2-K中通过双光子共振激发原子或双光子激发分子产生2~3∏_(?)—a~3∑_u~+扩散带辐射的实验结果,并对激发机制以及扩散带辐射随激发能量和温度的变化进行了讨论.     

599.2 nm diffuse band radiation generated by two-photon exciting molecular and atomic potassium

Diffuse band radiation around 599. 2 nm in K_2 was generated by the two photon pumping potassium dimers or by the two-photon resonant pumping atomic potassium with following atoms-molecules collision energy transfer. The pumping wavelengths are in a wide range of 697-745 nm. The relevant mechanisms were discussed.     

钠蒸汽中通过四波参量过程产生紫外相干辐射的光谱特性

本文报告在钠蒸汽中,通过四波参量过程在327nm,328nm,330nm及333nm处得到紫外相干辐射及对它们光谱特性的研究结果。其中333nm信号的可调谐范围较宽,是一可能应用的紫外相干光源。 关键词：     

Stimulated thermal scattering induced by two-photon absorption and experimental observation of stimulated Brillouin scattering in the UV region

An analysis of the results of previous studies of stimulated scattering of UV pulses in liquids has shown that they disagree with the theory of stimulated scattering. To resolve the inconsistency, stimulated scattering of XeCl excimer laser radiation (λ = 308 nm) with pulse duration τ ≈ 8 ns in liquid hexane is investigated experimentally. A theoretical analysis of the results obtained revealed a new nonlinear optical phenomenon: stimulated thermal scattering induced by the heating due to two-photon absorption, called two-photon stimulated thermal scattering (two-photon STS-2). The stimulated backscatter spectrum contains a previously unknown line corresponding to two-photon STS-2 and a newly discovered SBS line in the UV region. The line is observed in experiment on liquid hexane and is characterized by the frequency shift Ω_B = 0.33 cm^?1 relative to the pump wavelength λ = 308 nm, in complete agreement with the theory of stimulated Brillouin scattering (SBS). The spectral line called the SBS line in previous studies has a frequency shift much smaller than that predicted by the SBS theory and must be interpreted as an unshifted two-photon STS-2 line. When two-photon STS-2 is used to obtain a phase-conjugate wave, the phase-conjugation fidelity is lower than that achieved by using SBS because of thermal self-action and slow decay of the thermal grating.