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41.
Yb3+离子在氟化物玻璃中的红外光谱性质   总被引:1,自引:0,他引:1  
张军杰  李毛和  胡和方 《光学学报》1999,19(12):694-1697
根据测得的Yb^3+离子在氟锆酸盐玻璃(ZBLAN)中的吸收光谱和荧光光谱,分析了Yb^3+离子在氟锆酸盐玻璃中的吸收特性和发光特性;计算了Yb^3+离子的发射截面σe,讨论了Yb^3+离子的再吸收效应;增加Yb^3+离子掺杂浓度不会发生浓度淬灭效应。  相似文献   
42.
关放  张军杰  张雯  李洋  高瑞霞 《化学教育》2020,41(12):99-102
采用价层电子对互斥理论、价键理论、杂化轨道理论、分子轨道理论等共价键理论对三氧化硫分子各种成键的可能进行了推演,比较系统地分析了SO3分子的共价成键情况,得出SO3分子中的S原子采取sp2杂化,分子中存在正常σ键、配位σ键以及一个离域大π键的结论。  相似文献   
43.
A series of highly Er~(3+)/Yb~(3+) co-doped fluoroaluminate glasses have been investigated in order to develop a microchip laser at 1.54 μm under 980 nm excitation. Measurements of absorption, emission and upconversion spectra have been performed to examine the effect of Er~(3+)/Yb~(3+) concentration quenching on spectroscopic properties. In the glasses with Er~(3+) concentrations below 10 mol%, concentration quenching is very low and the Er~(3+)/Yb~(3+) co-doped fluoroaluminate glasses have stronger fluorescence of 1.54μm due to the ~4I_(13/2)→~4I_(15/2) transition than that of Er~(3+) singly-doped glasses. As Er~(3+) concentrations above 10 mol% in the Er~(3+)/Yb~(3+) co-doped samples, concentration quenching of 1.54μm does obviously occur as a result of the back energy transfer from Er~(3+) to Yb~(3+). To obtain the highest emission efficiency at 1.54μm, the optimum doping-concentration ratio of Er~(3+)/Yb~(3+) was found to be approximately 1:1 in mol fraction when the Er~(3+) concentration is l  相似文献   
44.
Er3+掺杂重金属氧氟硅酸盐玻璃的上转换发光研究   总被引:2,自引:3,他引:2       下载免费PDF全文
研究了Er3 掺杂重金属氧氟硅酸盐玻璃的吸收光谱、上转换光谱和拉曼光谱 ,分析了重金属氧氟硅酸盐玻璃中Er3 的上转换发光机理 .结果表明 :通过 975nm的激光二极管激发 ,在室温下同时观察到蓝光 (4 1 1nmj)、绿光(5 2 5和 5 4 3nm)和红光 (6 5 5nm) ,分别是由于Er3 离子2 H9 2 →4 I1 5 2 ,2 H1 1 2 →4 I1 5 2 ,4 S3 2 →4 I1 5 2 ,和4 F9 2 →4 I1 5 2 跃迁 .随Er2 O3浓度的增加 ,蓝光、绿光和红光的发光强度都增强 ,上转换发光机理主要涉及能量转移和激发态吸收 ,强烈的绿光和红光激发是由于双光子吸收过程 ,而微弱的蓝光是由于三光子吸收过程 .拉曼光谱发现 ,对Er3 离子在重金属氧氟硅酸盐玻璃中的上转换发光 ,玻璃结构中的PbF2 起到重要作用  相似文献   
45.
Frequency upconversion fluorescence property of Er^3 -doped oxychloride germanate glass is investigated. Intense green and red emissions centred at 525, 546, and 657nm, corresponding to the transitions ^2H11/2→4I15/2,^4S3/2→^4I15/2, and ^4F9/2→^4I15/2, respectively, were simultaneously observed at room temperature. The quadratic dependence of the 525, 546, and 657nm emissions on excitation power indicates that a two-photon absorption process occurs under 975 nm laser diode (LD) excitation. The Raman spectrum investigation indicates that oxychloride germanate glass has the maximum phonon energy at-805cm^-1. The thermal stability of this oxychloride germanate glass is evaluated by differential scanning calorimetry, and thermal stability factor AT(△T = Tx -Tg) is 187℃. Intense upconversion luminescence and good thermal stability indicate that Er^3 -doped oxychloride germanate glass is a promising upconversion laser material.  相似文献   
46.
The emission properties of 2-um region fluorescence of Tm^3+-Ho^3+ co-doped tellurite glasses are investigated. Introducing F- ions to the composition of tellurite glasses plays a positive effect on the 2-#m emission. A maximum intensity of 2-um emission is achieved when 1.5-mol% Tm2O3 and 1-mol% Ho203 concentration are doped in the glasses. The emission cross section and gain coefficient of the ^5I8-^5I7 transition of Ho^3+ are calculated. The emission cross section has a maximum of 1.29×10-20 cm^2 at 2048 nm wavelength. The results indicate that Tm&3+-Ho^3+ co-doped tellurite glasses are suitable for 2-um application.  相似文献   
47.
Three kinds of Er^3+-doped tellurite glasses with different hydroxyl groups are prepared by the conventional melt-quenching method. Infrared spectra are measured to estimate the exact content of OH^- groups in samples. The maximum phonon energy in glasses are obtained by measuring the Raman scattering spectra. The strength parameters Ωt (t = 2, 4, 6) for all the samples are calculated and compared. The nonradiative decay rate of the Er^3+ ^4I13/2 → ^4I15/2 transition are calculated for the glass samples with different phonon energy and OH^- group contents. Finally, the effect of OH^- groups on fluorescence decay rate of Er^3+ is analysed, the constant KOH-Er of TWN, TZPL and TZL glasses are calculated to be 9.2 × 10^-19 cm^4s^-1, 5.9 × 10^-19 cm^4s^-1, and 3.5 × 10^-19 cm^4s^-1, respectively.  相似文献   
48.
稀土离子掺杂的AlF3基氟化物玻璃   总被引:3,自引:0,他引:3       下载免费PDF全文
在800和970nm LD激发下,分别研究了Er3+单掺和Yb3+,Tm3+共掺的AlF3基(AYF,AZF)玻璃中上转换发光、能量传递和浓度猝灭.在Er3+掺杂的AlF3基玻璃,随着Er3+掺杂量的增加,红光与绿光上转换发光强度比(Ired/Igreen)增加,这被认为与两个Er3+离子 关键词: 稀土离子 氟铝酸盐玻璃  相似文献   
49.
Spectral characteristics of the amplified spontaneous emission (ASE) from a novel single mode Er~(3+) doped tellurite fiber with D-type cladding is reported in this letter. When pumped at 980 nm, an ASE source that has nearly a 100-nm flat FWHM bandwidth is obtained with a fiber length of 30-60 cm. Variation of ASE spectra with pump powers and fiber lengths are measured. Output power up to 2.0 mW is obtained with a launched pump power of 660 mW.  相似文献   
50.
在800nm激光二极管激发下,研究高掺杂Er^3+(摩尔比大于3%)的AlF3基(AYF、AZF)玻璃的红外-可见上转换发光性质。在AYF玻璃中,550nm绿光上转换最佳Er^3+掺杂摩尔比为6%,而在AZF玻璃中为12%。随着Er^3+掺杂量的增加,红光与绿光上转换发光强度比(Ir/Is)增加。这被认为与两个Er^3+离子(一个在4I0/2态、另一个在^4S3/2)的交叉弛豫过程有关。同时由于此  相似文献   
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