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Preparation and optical spectroscopy of phosphate glasses containing divalent europium ions 总被引:1,自引:0,他引:1
P2O5.BaO.Na2O.K2O glasses doped with various content of Eu2O3 were prepared using high temperature melting method, and the Eu2+ ions in the phosphate glasses were obtained with the aid of the reductive action of silicon powder. The fabricating conditions, fluorescence, excitation spectra of the glasses were then studied. The glasses containing europium show a broad emission band at 450 nm and sharp bands from 580 to 650 nm, and the co-existence of Eu2+ and Eu3+ is identified. Also, a good glass with a dominant proportion and large quantity of Eu2+ ions can be obtained by the reductive action of silicon powder and proper processing. 相似文献
44.
BaFCl0.5Br0.5:Sm2+的荧光特性分析 总被引:4,自引:2,他引:2
本文是对无机光谱烧孔的典型材料BaFCl0.5Br0.5:Sm2+的发光动力学过程进行的探索。通过实验得到了5D2、5D1、5D0→7F0的荧光强度、荧光衰减曲线随温度的变化关系,对5D2→4f5d带的热激活、5DJ间的无辐射弛豫,5DJ→7F0的辐射跃迁等过程进行了分析。 相似文献
45.
Optical Waveguides and micro-mirrors have been successfully induced inside fused silica glass and k9 glass,respectively,by focusing a 800nm femtosecond(fs)pulsed laser with a repetition rate of 1kHz,The change of refractive index was determined to be 0.001-0.008 in the fused silica glass and 0.006 in the k9 glass.The refractive index change is dependent on both the dose of irradiation and the power density of the fs pulsed laser,Photoluminescence was observed in the irradiated region,and was attributed to the defects induced by fs laser irradiation.We discuss the relationship between the optical property and the luminescent propert property of the irradiated region. 相似文献
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MgO对Sr2SiO4:Eu2+荧光粉发光性质的影响 总被引:1,自引:1,他引:0
通过在Sr2SiO4:Eu2+荧光粉中加入MgO,提高了Sr2SiO4:Eu2+荧光粉的蓝光和黄光发射带的发射强度,研究了MgO浓度对Sr2SiO4:Eu2+荧光粉发光强度的影响。当Mg与Si的量比在1.0附近时,荧光粉的亮度较高,且发光颜色为白色。通过调节Sr2SiO4:yEu2+ ,MgO荧光粉中Eu2+的掺杂浓度,可以调节荧光粉的发光颜色。用Sr2SiO4:Eu2+ ,MgO和400 nm的InGaN管芯制备的白光LED,色坐标优于α'-Sr2SiO4:Eu2+和β-Sr2SiO4:Eu2+荧光粉制成的白光LED,显色指数和流明效率高于β-Sr2SiO4:Eu2+和α'-Sr2SiO4:Eu2+制成的白光LED。 相似文献
48.
The blue-shifted supercontinuum generation in a photonic crystal fiber pumped by high peak power femtosecond pulses with wavelength located in the anomalous dispersion region is investigated experimentally and numerically. The formation of a blue-shifted enhanced supercontinuum due to the pulse collapse is demonstrated. The process of the pulse collapse is measured by using the grating-eliminated no-nonsense observation of ultrafast incident laser light e-fields technique (GRENOUILLE). Numerical simulations in spectral and temporal domains are conducted. The data from numerical simulations are in good agreement with the experimental results. Our experimental results and numerical simulations show that the pulse collapse is the determining factor in the generation of blue-shifted supercontinuum. 相似文献
49.
纳米Y2O3:Eu3+中S6格位电荷迁移带的光学特性 总被引:3,自引:2,他引:1
在Y2O3:Eu^3 体材料和纳米材料中,观察到紫外激发下处于S6格位的Eu^3 的^5D0→^7F1发射(582nm)的强度,相对处于C2格位的^5D0→^7F0发射(580nm)的强度,随着激发波长在200—300nm紫外区由长变短而增强。这一现象说明Y2O3:Eu^3 中两种格位的电荷迁移带及基质激发的性质不同。光谱分解得出S6格位的电荷迁移带位于C2格位电荷迁移带的高能侧,Y2O3基质倾向于向S6格位进行能量传递。与体材料相比,两种格位的电荷迁移带在纳米材料中都发生红移;相对于C2格位的电荷迁移带,S6格位的电荷迁移带强度在纳米材料中比在体材料中明显降低,并对结果进行了讨论。 相似文献
50.
The femtosecond temporal speckle field of a random medium is
studied theoretically and experimentally. Femtosecond temporal
speckle arises from the interference of multiple randomly scattered
electric fields. The femtosecond temporal speckle field is measured with
a cross-correlation frequency-resolved optical gating method. The
spatial average of the speckle field yields a smooth transmitted
profile. The speckle field is a circular complex Gaussian variable
because the scattered light beams from different trajectories have
no correlation with each other. The field and the intensity profiles
of individual speckle spots fluctuate randomly in time. The ensemble
average of the temporal intensity profiles converges, thereby
yielding the photon travel time probability distribution
function. 相似文献