302 resultados para Diagramma E-R redattore ER modello relazionale SharpER


Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Three kinds of new nickel(II) complexes of alpha-isoxazolylazo-beta-diketones with blue-violet light absorption were synthesized. Their structures were postulated based on elemental analysis, MS and FT-IR spectra. Smooth films on K9 glass substrates were prepared using the spin-coating method. The absorption properties and thermal stability of these complexes were discussed. The static optical recording test for high density digital versatile disc-recordable (HD-DVD-R) system was also studied. (c) 2005 Elsevier B.V. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

在组成为15Li2O-15Nb2O5-70TeO2-0.1Er2O3-0.4Yb2O3(%, 摩尔分数)的碲酸盐玻璃基础上, 采用两步热处理法制备了透明的含纳米晶颗粒碲酸盐玻璃陶瓷. 通过X射线衍射(XRD)测试表明, 玻璃陶瓷中的晶体颗粒组成为Yb6Te5O19.2或Er6Te5O19.2, 晶粒尺寸约为55 nm. 根据Judd-Ofelt理论计算了Er^3+离子在基质玻璃和玻璃陶瓷中的光谱参数Ωt(t=2, 4, 6)以及Er^3+:4I15/2→4I13/2跃迁自发辐射几率, 根据McCumber

Relevância:

20.00% 20.00%

Publicador:

Resumo:

测试了掺铒碲酸盐玻璃在不同掺杂浓度下的荧光特性.根据Dexter能量转移理论计算了Er^3+在碲酸盐玻璃中发生浓度猝灭的临界距离R0及Er^3+间相互作用参数CEr-Er,并与其他基质玻璃中CEr-Er数值进行了比较.最后建立了Er^3+基于OH^-作为猝灭中心下碲酸盐玻璃中的浓度猝灭模型.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

制备了四种不同铒离子掺杂浓度的碲酸盐玻璃,通过测定吸收光谱计算了吸收谱线的振子强度,根据Judd-Ofelt理论计算了不同浓度下Er^3+离子发光光谱的强度参数Ω(i=2,4,6),计算了自发辐射电偶和磁偶跃迁概率、辐射寿命、荧光分支比等参数,讨论了Er^3+离子浓度变化对以上这些参数的影响。测试了Er^3+:^4I13/2→^4I15/2跃迁对应的荧光光谱和Er^3+:^4I13/2能级荧光寿命。最后应用McCumber理论计算了玻璃中Er^3+:^4I13/2→^4I15/2跃迁对应的受激发射截面大小

Relevância:

20.00% 20.00%

Publicador:

Resumo:

熔制了掺铒碲铌玻璃样品(100-X)TeO2-XNb2O5(X=5,10,15,20mol%),测试了其密度、折射率、转变温度、析晶温度、维氏机械强度、吸收光谱、荧光光谱、荧光寿命等参量。利用Judd-Ofelt和McCumber理论分别计算了铒离子强度参量Ωt(t=2,4,6)和受激发射截面σcmi的大小,研究了掺铒碲铌玻璃样品光谱参量对Nb2O5成分的依赖性,并与典型的碲锌钠玻璃(75TeO2-20ZnO-5Na2O)在热学、机械强度、光谱性质和放大品行四个方面进行了比较.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

探求新的具有优良的热学和光学性能的基质玻璃系统,是获得具有宽带宽和增益平坦的掺Er^3+光纤放大器(EDFA)的一种有效途径。制备了一种新型氧氟碲酸盐玻璃TeO2-BaF2-LaF3,并对其热学性能和光学性质进行了测试。应用乍得-奥菲尔特(Judd-Ofelt)理论计算了Er^3+离子的J-O理论参量和荧光寿命r。探讨了氟化物的引入对碲酸盐玻璃结构的改变的影响,并分析了其对玻璃的热学性质和光学性质的影响。实验发现,获得的氧氟碲酸盐玻璃具有优良的热学稳定性(△T=156.6C),宽的荧光半峰全宽(72nm)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

制备了掺Er^3+-TeO2-ZnO-Na2O-Nb2O5和TeO2-PbO-B2O3系统玻璃,测定了玻璃的热稳定性和吸收光谱,在碲-锌-钠多组分玻璃中具有不同的玻璃转变温度Tg和开始析晶温度Tx,按照Hruby’s参数HR=(Tx-Tg)/(T1-Tc);(Tx-Tg)越大则玻璃稳定性越好,在TeO2-ZnO-Na2O系统玻璃中ZnO含量增加则(Tx-Tg)增大,加入少量(小于10%(摩尔分数))Nb2O5,PbO使(Tx-Tg)变大,玻璃的热稳定性变好。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The integrated absorption cross section Sigma(abs), I peak emission cross section sigma(cmi), Judd-Ofeld intensity parameters Omega(iota) ( t = 2,4,6), and spontaneous emission probability A(R) of Er3+ ions were determined for Erbium doped alkali and alkaline earth phosphate glasses. It is found the compositional dependence of sigma(emi) 5 almost similar to that of Sigma(abs), which is determined by the sum, of Omega(1) (3 Omega(2) + 10 Omega(4) + 21 Omega(6)). In addition, the compositional dependence of Omega(1) was studied in these glass systems. As a result, compared with. Omega(4) and Omega(6) the Omega(2) has a stronger compositional dependence on the ionic radius and content of modifers. The covalency of Er-O bonds in phosphate glass is weaker than that in silicate glass, germanate glass, aluminate glass, and tellurate glass, since Omega(6) of phosphate glass is relatively large. A(R) is affected by the covalency of the Er3+ ion sites and corresponds to the Omega(6) value.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

测量了不同掺杂浓度下Er^3+离子在碲酸盐玻璃中的吸收光谱、发射光谱和Er^3+离子的荧光寿命,计算了Er^3+离子的发射截面σc,分析了Er^3+离子掺杂浓度对其发光强度和荧光寿命的影响.结果表明,Er^3+离子掺杂浓度较低时,对其荧光强度和荧光寿命没有显著的影响;掺杂浓度高时,出现了浓度猝灭效应,使Er^3+离子荧光光强度降低,荧光寿命下降.实验确定了掺杂浓度最优值,同时对浓度猝灭机制进行了分析.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

研究了Cr^3+,Yb^3+,Er^3+共掺磷酸盐铒玻璃转镜调Q激光性质.三种Er2O3掺杂浓度的激光实验结果表明,在Er2O3名义掺杂浓度为0.5wt%时,玻璃的综合激光性质最好,重复频率为0.1Hz时,它的激光阈值功率为14.5mJ,最大输出能量为9.6mJ,斜率效率为0.55%.在同种实验条件下,比较了Cr14和Kigre公司生产的QE-7S激光性质参数,实验表明,前者激光阈值功率稍低,而后者的斜率效率和最大输出功率略高.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

以Yb^3+-Er^3+共掺的P2O5-B2O3-R2O-MO-Al2O3(R=Li,Na,K;M=Zn,Ca,Sr,Ba)系统玻璃为研究对象,分别分析了改变B2O3,的含量,以及加入不同种类的碱金属和碱土金属氧化物对玻璃的物理化学性质的影响。研究结果表明,当B2O3的含量增加,玻璃的Tg,Tf上升,热膨胀系数下降;随着修饰体阳离子半径减小,玻璃的溶解速率下降,化学稳定性变好。

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fluorophosphate glass with 4 mol.% ErF3 content was prepared. The different scanning calorimetry was conducted. Raman spectrum, infrared transmission spectrum, absorption spectrum were measured. Fluorescence spectrum and lifetime of emission around 1.53 mu m were measured under 970 nm laser diode excitation. The metaphosphate content in the composition is limited, but the maximum phonon energy of glass amounts to 1290 cm- 1, and is comparatively high. The full width at half maximum is about 56 nm, and is wider than for most of the materials investigated. The measured lifetime of I-4(13/2) -> I-4(15/2) transition, contributed by the high phonon energy, inefficient interaction of Er3+ ions, and low water content, amounts to no less than 7.36 ms though the Er3+ concentration is high. This work might provide useful information for the development of compact optical devices.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We study the nonlinear photonics of rare-earth-doped oxyfluoride nanophase vitroceramics (FOV), oxyfluoride glass (FOG), and ZBLAN fluoride glass. We found that an interesting fluorescence intensity inversion phenomenon between red and green fluorescence occurs from Er(0.5)Yb(3):FOV The dynamic range Sigma of the intensity inversion between red and green fluorescence of Er(0.5)Yb(3):FOV is about 5.753 x 10(2), which is 100 to 1000 times larger than those of other materials. One of the applications of this phenomenon is double-wavelength fluorescence falsification-preventing technology, which is proved to possess the novel antifriction loss and antiscribble properties. (c) 2007 Optical Society of America.