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1.
Theoretical Calculations of Transition Probabilities and Oscillator Strengths for Sc(III) and Y(III)
利用最弱受约束电子势模型理论计算了二价钪离子和二价钇离子的能级间跃迁几率和振子强度的数值. 二价钪离子的计算结果与美国国家标准技术研究院(NIST)所给出的可接受值吻合良好. 二价钇离子的计算结果也与现有的其他理论方法的计算结果十分接近. 相似文献
2.
氖,硅和钛元素的类锂离子激发态参数的计算 总被引:1,自引:0,他引:1
杨治虎 《原子与分子物理学报》1994,11(3):330-334
为利用本所重离子加速器原子物理实验装置进行高电离态离子物理实验研究,本文采用郑能武等人^[^1^]提出的最弱受约束电子势模型理论的波函数和H.A.Bethe等入^[^2^]的量子力学理论,估算了Ne,Si和Ti离子的类锂等电子序2S-2P态的跃迁几率和振子强度,并把计算结果与文献结果作了比较。 相似文献
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研究最弱受约束电子势模型的散射态,获得了精确的按“k/2π标度”归一化的散射态波函数以及相移表达式,给出了束缚—自由非相对论跃迁矩阵元的解析计算公式。这些结果可广泛应用于处理原子的散射问题之中。 相似文献
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研究最弱受约束电子势模型的散射态,获得了精确的按“k/2π标度”,归一化的散射态波函数以及相移表达式。给出了束缚-自由非相对论跃迁矩阵元的解析计算公式。这些结果可广泛应用于处理原子的散射问题之中。 相似文献
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应用简单的方法———Laplace变换法来求最弱受约束电子势模型(WBEPM势)的径向Schrdinger方程.通过这种方法使得两阶微分方程变为一阶微分方程,这样可以直接运用积分得到WBEPM势束缚态能量方程和归一化的波函数,所得结果与文献一致.更重要的是用Laplace变换得到径向波函数的两类新的递推关系.这种递推关系是有效主量子数和角量子数之间关系,在计算原子和分子跃迁几率时有着广泛的应用. 相似文献
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(LaO)3BO3中Eu^3+和Sm^3+的光致发光 总被引:4,自引:2,他引:2
研究了紫外光激发下,(LaO)3BO3基质中Eu^3+和Sm^3+的光谱性质,Eu^3+和Sm^3+的电荷迁移激发带及发光强度随组成和结构变化的规律性,并探讨了Eu^3+和Sm^3+自身浓度猝灭的机理。 相似文献
12.
采用微乳液法合成了Ce3 ,Tb3 单掺和双掺KZnF3纳米晶。分析了样品的结构与形态,结果表明,所合成的样品均为单相,颗粒粒度分布均匀。讨论了光谱特性,并与高温固相法合成的产物作了对比。研究发现,KZnF3:Ce3 纳米晶的发射光谱与体相多晶相比,最强峰位置红移约35nm;在KZnF3纳米晶双掺体系中存在Ce3 →Tb3 能量传递,尤其是Tb3 的5D4→7F5跃迁发射显著增强,有望成为一种有发展前途的绿色荧光材料。 相似文献
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Polycrystalline GdAl3(BO3)4 phosphors codoped with Yb3+/Tb3+ and/or Nd3+/Yb3+/Tb3+ have been synthesized by combustion method. Upon excitation with a 980 nm laser diode, an intense green upconversion luminescence
has been observed in GdAl3(BO3)4:Yb,Tb phosphor. The quadratic dependence of the luminescence on the pump-laser power indicating a cooperative energy transfer
process. Meanwhile, it is noticed that upon excitation with 808 nm laser diode, intense luminescence has clearly been detected
in GdAl3(BO3)4:Nd,Yb,Tb phosphor. The luminescence intensity exhibits also a quadratic dependence on incident pump-laser power. However,
no green-emission has been observed in GdAl3(BO3)4 phosphors codoped with Yb3+/Tb3+ or Nd3+/Tb3+ respectively upon excited at 808 nm laser diode. A proposed upconversion mechanism involving energy transfer from Nd3+ to Yb3+, and then a cooperative energy transfer process from two excited Yb3+ to Tb3+ has been presented. 相似文献
14.
O_3 fast and simple treatment-enhanced p-doped in Spiro-MeOTAD for CH_3NH_3I vapor-assisted processed CH_3NH_3PbI_3 perovskite solar cells 下载免费PDF全文
We demonstrate a simple and fast post-deposition treatment with high process compatibility on the hole transport material(HTM) Spiro-MeOTAD in vapor-assisted solution processed methylammonium lead triiodide(CH_3NH_3PbI_3)-based solar cells. The prepared Co-doped p-type Spiro-MeOTAD films are treated by O_3 at room temperature for 5 min,10 min, and 20 min, respectively, prior to the deposition of the metal electrodes. Compared with the traditional oxidation of Spiro-MeOTAD films overnight in dry air, our fast O_3 treatment of HTM at room temperature only needs just 10 min,and a relative 40.3% increment in the power conversion efficiency is observed with respect to the result of without-treated perovskite solar cells. This improvement of efficiency is mainly attributed to the obvious increase of the fill factor and short-circuit current density, despite a slight decrease in the open-circuit voltage. Ultraviolet photoelectron spectroscopy(UPS) and Hall effect measurement method are employed in our study to determine the changes of properties after O_3 treatment in HTM. It is found that after the HTM is exposed to O_3, its p-type doping level is enhanced. The enhancement of conductivity and Hall mobility of the film, resulting from the improvement in p-doping level of HTM, leads to better performances of perovskite solar cells. Best power conversion efficiencies(PCEs) of 13.05% and 16.39% are achieved with most properly optimized HTM via CH_3NH_3I vapor-assisted method and traditional single-step method respectively. 相似文献
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1.55 μm波段是光通讯的一个重要波段,而且对人眼安全,有高的大气透过率,因此可以广泛应用于通讯和遥感测距等领域。由于Er3+离子对商品化的InGaAs激光二极管的抽运波长不能有效吸收,因此一般通过在基质中共掺杂Yb3+和Er3+离子来获得1.55 μm波段激光输出。采用助熔剂法生长了不同Yb3+和Er3+掺杂浓度的YAl3(BO3)4(YAB)晶体。运用速率方程模型研究了晶体中Yb3+到Er3+能量传递过程,得到了根据Yb3+离子的荧光寿命计算能量传递系数的简单计算公式。计算了不同掺杂离子浓度的YAB晶体中的能量传递系数等相关参数。结果表明,在YAB晶体中,Yb3+到Er3+能量传递非常有效,YAB晶体可以作为一种能获得1.55 μm激光输出的良好介质材料。 相似文献
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利用具有钙钛矿结构的有机-无机杂化卤化物制备的太阳能电池, 由于具有溶液可加工性和高光电转换效率, 受到了广泛关注. 在目前报道的最高光电转换效率的器件中, 采用了CH3NH3PbI(3-x)Clx碘氯混合钙钛矿作为吸光层, 据报道在这种材料中光电子的扩散长度可以超过1 μm. 本文综述了在CH3NH3PbI(3-x)Clx方面现有的研究工作, 指出了薄膜制备条件的重要性, 并研究了CH3NH3I在PbCl2/CH3NH3I热解法制备CH3NH3PbI(3-x)Clx吸光层中的作用. 扫描电子显微镜研究表明CH3NH3I加入量为PbCl2的2倍到2.75倍时, CH3NH3I加入量的增加可以提高CH3NH3PbI(3-x)Clx吸光层的覆盖度和结晶度, CH3NH3I加入量进一步增加到3倍时, 形貌变化不大. X射线光电子能谱的数据证实了CH3NH3I加入量对覆盖度的影响, 并显示在CH3NH3I加入量大于PbCl2的2.5倍以后, CH3NH3PbI(3-x)Clx中氯的掺入量急剧下降. 光电测试表明器件性能随CH3NH3I加入量增加而增加, 在CH3NH3I/PbCl2为3/1时达到最高, 加入量略小于3/1对性能影响不大. 相似文献
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Summary We report the measurements of the3
D(3s4d)-3
P(3s3p)3
D(3s5d)-3
P(3s3p), and3
P(3p
2)-3
P(3s3p) transition frequency of MgI, the fine-structure separation and isotope shift between24Mg and26Mg. The measurements have been performed in a metastable atomic beam; a good agreement is found for data already existing
in the literature. The accuracy of the measurements reported in this paper is mainly limited by the Doppler broadening of
theI
2 transitions used as a reference and by the precision in the knowledge of the related wavelengths. 相似文献
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镱铒共掺Al2O3薄膜光致发光特性优化 总被引:3,自引:1,他引:2
用中频磁控溅射方法在SiO2/Si基底上制备了五组固定掺铒浓度不同镱铒浓度比率的镱铒共掺Al2O3薄膜样品.室温下测量了薄膜在1.430 μm~1.630 μm波段范围内光致发光光谱.研究发现,镱的掺入有效地提高了三价铒离子的光致发光强度,最优的镱铒掺杂为:掺铒0.33 mol%,Yb3+∶Er3+=10∶1,比相同掺铒浓度单掺铒样品光致发光峰值强度增强40倍;确定的掺铒浓度,有着固定的最佳镱铒浓度比率,主要是镱铒离子间的正向和反向能量传递相互作用的结果,但最佳镱铒浓度比率随着掺铒浓度的增加呈现下降趋势;单掺铒薄膜的光致发光峰值强度随掺铒浓度呈现近Gauss形状变化,而最佳镱铒共掺样品的光致发光峰值强度随掺铒浓度呈现了倒Gauss形状变化. 相似文献
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P. Steiner R. Zimmermann F. Reinert Th. Engel S. Hüfner 《Zeitschrift für Physik B Condensed Matter》1995,99(1):479-490
3s- and 3p-core level excitations for a large number of 3d-transition metal oxides, with a formal 3d occupation from 3d0 to 3d10, have been measured by electron energy loss spectroscopy in reflection geometry (REELS) with primary energies 200 eV≤E
0≤1600 eV. Their intensities decrease systematically with the formal 3d-count, classifying them as transitions to empty 3d-states.
The structure of the 3s excitations is analysed in detail and is compared to the 3s-XPS photoemission spectra of the samples.
This 3s-REELS structure and its change with the 3d occupation can be explained by the assumption that the excitation arises
mainly from a 3s23dn→3s13dn+1 quadrupole transition. 相似文献
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本文研究了单掺(Sm3+,Ce3+、Gd3+.Sb3+、双掺(Sm3++Ce3+、Sm3++Gd3+,Sm3++Sb3+)和兰掺(Sm3++Gd3++Ce3+)约四十余种不同玻璃的发射谱和激发谱.探讨了玻璃成份和掺杂离子浓度对Sm3+发光性质的影响以及Ce3+,Gd3+、Sb3+、Ce3++Gd3+对Sm3+的敏化作用。 相似文献