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制备了Tm3+/Yb3+共掺TeO2-PbO-ZnO-La2O3玻璃,研究了玻璃红外吸收光谱和980 nm激光抽运下上转换发光光谱,分析了上转换发光机制.基于Tm3+和Yb3+的能级图及上转换机制建立了速率方程,得出了稀土离子各能级的粒子数分布密度以及Tm3+与Yb3+之间的能量转移系数Cbi(i=0,1,3).结果表明,随着PbO加入,Yb3+:2F5/2与Tm3+:3H4间的能量转移不断增加,上转换蓝光的发光强度明显增强. 相似文献
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在PbSe/UV胶量子点光纤环形腔激光器实验的基础上,通过建立并数值求解粒子数速率方程和光功率传播方程等,对1550nm的激光输出特性进行了数值模拟。计算的抽运阈值功率、单/多模激光输出功率随抽运功率的变化、合适的PbSe掺杂浓度、单模激光功率随输出耦合比的变化等,与实验结果基本吻合。通过对PbSe量子点光纤中激光功率分布的研究,给出了粒子数密度的反转条件:N2/N1≥0.45,该条件可由1550nm波长处粒子数反转的吸收截面与辐射截面之比得到。研究了掺杂浓度对激光功率的影响,给出了合适的掺杂浓度范围。 相似文献
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基于传输速率方程,对Ho3+:ZBLAN光纤激光器的动态特性--上能级粒子数以及输出激光功率的弛豫振荡特性进行了数值分析.通过忽略光纤参数对传输方向的依赖性,抽运光和信号光的功率传输方程被分别简化处理.结果表明,在5I6能级的粒子数首先经历一次弛豫振荡后,5I6和5I7能级的粒子数交替弛豫振荡并达到稳态;同样,在3μm波长的激光功率首先经历一次弛豫振荡后,3μm和2μm波长的激光功率交替弛豫振荡并达到稳态,而且,弛豫振荡时的峰值功率远大于稳态时的激光功率. 相似文献
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结合激光微观动力学和热传学,充分考虑到发射激光时的各能级粒子数和热力学分布特性,建立了用于分析二极管抽运铷金属蒸气激光物理特性和增益腔内的温度分布模型,得到了抽运功率和激光输出、光-光转换效率及各物理参数之间的关系,分析了有效提高抽运能量吸收的具体措施,揭示了2P3/2和2P1/2两个精细能级之间的集居数弛豫对半导体抽运碱金属蒸气激光器(DPAL)物理特性的影响。结果表明:在设计不同用途DPAL时,必须要综合考虑各种因素,以确定相应的最佳结构参数。 相似文献
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用波长为623.8nm的He-Ne激光作信号光和一束泵浦光,用波长为488.0nm的Ar+激光作另一束泵浦光,在Eu:Fe:LiNbO3晶体中实现了非简并四波混频,获得了波长为488.0nm的变频相位共轭光,同时还产生了波长为632.8nm的同频相位共扼光。本文对上述实验结果进行了定性分析。 相似文献
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激光扫描捕获系统通过对激光光源进行扩束变换,压缩光源的发散角度,可减少在远距离传输中的能量损失。为满足某通信实验需要,设计一种放大倍率为10倍,光源扫描视场为4840的小型扩束系统。系统要求在1 550 nm、1 064 nm、800 nm和632.8 nm激光波段,全视场范围内波像差RMS不大于0.1(=632.8 nm),且无中心遮拦。通过计算初始结构参数,利用Zemax软件优化,采用4片反射式非球面进行设计,全系统体积约为9010060 mm3,波像差最大为0.095,满足系统尺寸和像质要求,整个系统光能透过率约为92%,满足透过率大于85%的设计要求。 相似文献
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The image formation and the spectral resolution of a 5m echelle spectrometer were investigated. As shown in this study, the
spectrometer operates approximately diffraction-limited in the visible and uv, whereas in the vacuum uv (120.0 nm) the resolving
power is still >54% of the diffraction-limited value. The spectrometer was designed according to the results of an analytical
imaging theory. Residual optical aberrations were investigated by measuring the image distributions at four wavelengths between
120.0 and 632.8 nm (grating replaced by a plane mirror), in order to experimentally test the reliability of these theoretical
results in combination with the influence of the imperfections of the optical components. The ratios of 40%-widths of the
measured image distributions in the exit slit plane to the corresponding theoretical values were determined to be 0.56 at
120.0 nm, 0.68 at 174.0 nm, 0.74 at 257.3 nm, and 0.99 at 632.8 nm. Due to a lack of suitable light sources in the vacuum
uv with sufficiently small band widths, the instrumental functions of the spectrometer could only be measured at 257.3, at
514.5, and at 632.8 nm, using stabilized and frequency doubled laser lines. The resolving powersR, which were deduced from the 40%-widths of the measured instrumental functions, were determined to be 1.42×106 [0.80] at 257.3 nm, 0.86×106 [0.97] at 514.5 nm, and 0.71×106 [0.98] at 632.8nm (ratiosR
exp/R
theor in brackets). The comparatively high resolving powerR≳0.02×106 [0.54] at 120.0 nm was estimated from the 40%-width of the measured image distribution. 相似文献
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采用水中抛光技术抛制了90mm×60mm×10 mm的K9玻璃基片,表面粗糙度达1nm。在APS1504镀膜机上,摸索了电子束蒸发镀膜的最佳工艺条件,较稳定地在该超光滑玻璃表面上镀制了对波长1054 nm、入射角45°、反射率R≥99.5%的反射膜。膜层的抗激光损伤阈值可达26 J/cm2(1054nm, 1ns),镀膜后该玻璃基片反射波前可达l /10(p-v),最终制备了超高阈值Pick-off反射镜。 相似文献
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LIU Chunling WANG Yuxiao SHAN Honglin WANG Jun ZHA Zizhong WANG Qi 《Chinese Journal of Lasers》1999,8(1):92-96
1IntroductionInrecentyears,thepotentialofreversesaturableabsorption(RSA)materialsinopticallimitingandopticalswitchinghavegrad... 相似文献
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Visible and near-infrared optical properties of Nd:CLNGG crystal waveguides formed by proton implantation
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A Nd:CLNGG waveguide structure operated at wavelengths of both 632.8 nm and 1539 nm was demonstrated for the first time to our knowledge, which was produced by the 480-keV H~+ion implantation with a dose of 1.0×10~(17)protons/cm~2.Its propagating modes at 632.8 nm and 1539 nm were measured by the well-known prism coupling technique. The refractive index profile at either 632.8-nm wavelength or 1539-nm wavelength was optical barrier type in the proton-implanted Nd:CLNGG crystal optical waveguide, which was calculated by using the reflectivity calculation method. The near-field light intensity distributions were also simulated by the finite-difference beam propagation method in the visible and nearinfrared bands. 相似文献
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The irradiation of human lymphocytes with a He-Ne laser(632.8nm,56J/m~2) elevated the DNA synthesis levol in phytohemagglutinin-treated cells,but didnot itself cause the blasttransformation.The boosting effect of irradition was especiallypronounced in case of suboptimal PHA concentrations(0.5and 1μg/ml). 相似文献
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The high-fluorescence background of jade creates a great impact on the Raman spectra measurements that impedes their application in jade analysis and treatment, particularly with ancient jade. The five most important materials of Chinese ancient jade are amphibole, serpentine, turquoise, agate/chalcedony, and anorthite-zoisite (Dushan jade). This study comparatively analyzed the Raman spectra of different wavelengths' excitation light sources (514.5 nm, 632.8 nm, 785 nm) in identifying these Chinese jades, and this article discusses the most applicable ones to the analysis of different jade materials. The results show that although 632.8 nm He-Ne laser is appropriate for turquoise jades, generally speaking, Raman spectra produced by the 785 nm semiconductor laser and the 632.8 nm He-Ne laser are better for most kinds of jades than the spectra produced by the 514.5 nm argon ion laser, and both of them can be effectively used jointly in research by nondestructive phase analysis of Chinese ancient jade. 相似文献