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51.
对掺铜0.2~1.0wt%三种含不同Cu~+离子浓度的磷酸盐玻璃,在室温和77K下作了时间分辨萤光光谱和萤光寿命的测定。用紫外220nm或320nm激发,在不同Cu~_+离子浓度时,光谱性质都不一样。室温下220nm激发时,谱线较宽。并随延迟时间增加,谱线移向长波,线宽增加。320nm激发时,谱线无变化。低温下谱线的变化速率较慢。另外,在Cu~+离子浓度增加时,谱线的变化趋势不尽相同,且变化速率和幅度均增加。 萤光寿命的测定结果显示激发态离子的衰减速率与发射波长有关。发射波长愈短,衰减愈快。低温下衰减速率随发射波长的变化比室温下更甚。 本文用能量转移机理解释了实验现象。认为声子支助的离子-离子相互作用,使激发从高能隙格位迁移到低能隙格位。 相似文献
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The mechanism of near infrared (IR) focused femtosecond (fs) laser induced defects in silica glasses produced by different methods is systematically investigated through measurements of absorption, fluorescence, and electronic spin resonance (ESR) spectra. The influence of impurities and hydroxyl groups on defects is discussed. The results show that ES silica glasses containing high OH and few defects are much stable under fs laser irradiation. It is also verified that Si E_δ~′center formation has no direct relation with chloride ions. 相似文献
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The mechanism of near infrared (IR) focused femtosecond (fs) laser induced defects in silica glasses produced by different methods is systematically investigated through measurements of absorption,fluorescence, and electronic spin resonance (ESR) spectra. The influence of impurities and hydroxyl groups on defects is discussed. The results show that ES silica glasses containing high OH and few defects are much stable under fs laser irradiation. It is also verified that Si E'δ center formation has no direct relation with chloride ions. 相似文献
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Spectroscopy and Optical Properties of Novel Metal(Ⅱ)-Azo Complex Films in Blue-Violet Light Region
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A novel azo derivative,α-(2-azoxyisoxazole)-β-diketone derivative (ADD),and its copper (Ⅱ) and nickel (Ⅱ) complex (CuADD and NiADD) films have been prepared respectively by spin-coated method.The absorption spectra of the films on a K9 glass substrate in the 300-800 nm wavelength region have been measured.The optical constants (complex refractive index N=n iκ) and thickness of the complex films on a single-crystal silicon substrate in the 300-600nm wavelength region have been investigated on an improved rotating analyser-polariser (RAP) type of scanning ellipsometer,and the dielectric constants ε(ε=ε1 iε2),absorption coefficients α as well as reflectance R of the films were calculated.It is found that the absorption maxima of the ADD,CuADD and NiADD films are at 324nm,372nm and 385nm,respectively,and small absorption values and steep absorption band edges of the CuADD and NiADD films are observed at the 405nm side;The CuADD and NiADD films give high n values of 2.08 and 1.98,and low κ values of 0.2 and 0.28,respectively,at 405nm,and their thicknesses are in the range of 130-150nm;the high reflectivity of 58.5% and 45.5% of the CuADD and NiADD films with Ag as a reflective layer were obtained at the film thicknesses of 70 nm and 80nm respectively.These results show that the novel CuADD and NiADD films seem to be a very promising organic recording material for the next generation of high density digital versatile disc-recordable (HD-DVD-R) systems that use a high numerical aperture of 0.85 at 405nm wavelength. 相似文献
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利用Ar离子激光器激发掺Nd3+和Er3+的氟化物玻璃,获得了近紫外的上转换发光.测量了上转换荧光的功率特性和浓度特性.阐述了紫外上转换的能级跃迁过程,并与理论作了对比. 相似文献
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对掺钛氟磷酸盐玻璃作了吸收光谱,荧光光谱和激发光谱的测定。该玻璃中,Ti~(3+)离了处于畸变八面体格位中。用紫外250~320nm电荷迁移带激发,可观察到可见区~0.55μm的发光。带宽~180nm,激发光谱的峰值位于290nm。同时分别测定了室温和77K时Ti~(3+)的时间分辨荧光光谱及弛豫光谱。随着延迟时间增加,低温下荧光峰值从510nm向长波方向移动到640nm。光谱显得弥散。而室温下变化较小。低温下荧光寿命为5~12μs,与发射波长有关。相反,室温下荧光寿命均为13μs,与发射波长无关。本文还对无机玻璃中Ti~(3+)的发光条件和可能性作了讨论。 相似文献
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