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31.
Alternate pulsed laser deposition from the host (Al2O3) and dopant (Er, Yb) targets has been used to prepare artificially nanostructured films in which the rare earth ion-ion separation is controlled in the nanometer scale in order to control energy transfer between ions. One series of films was prepared in the standard on-axis configuration, i.e. a static substrate being centred with respect to the plasma expansion axis. A second series of films was prepared by rotating the substrate with respect to a shifted axis parallel to the plasma expansion one (off-axis configuration). The latter configuration leads to films with enhanced thickness and Er related photoluminescence intensity uniformity. More interestingly, the Er related photoluminescence lifetime in as-grown films increases up to 2.5 ms, which is much higher than the maximum value of 1 ms obtained for the on-axis configuration films. This enhancement is discussed in terms of a decrease of defect density when using the off-axis configuration. 相似文献
32.
YANG Peizhi DENG Peizhen HUANG Guosong ZHAO Zhiwei CHEN Wei XU Jun 《Chinese Journal of Lasers》2000,9(1):91-96
1 Introduction Recently,withthedevelopmentofhighperformanceInGaAsdiodelasersinthewavelengthrangebetween0.9and1.1μm[1],greatatte... 相似文献
33.
采用固相反应方法,制备了Er3+离子浓度为0.5 at.%,Yb掺杂浓度范围为0.0— 6.0 at.%的Er/Yb共掺激光玻璃,并对激光玻璃的吸收光谱和光致荧光光谱进行了分析.研究 结果显示,Yb3+掺杂对Er3+在980 nm附近的吸收起到了非常显著的 增强作用.在 980 nm的激光抽运下,激光玻璃在1530 nm处的光致发光强度随着Yb离子浓度 的增加而先增大后减小, 当Yb3+离子浓度为Er3+离子浓度6倍时光 致发光强度达到最大值.同时还发现了Yb3+对Er3+的光致荧光光谱 的展宽作用,并讨论了荧光光谱的展宽机理.
关键词:
Er/Yb共掺玻璃
光致发光
吸收光谱 相似文献
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36.
镱的原子吸收分析进展 总被引:1,自引:0,他引:1
米瑞华 《光谱学与光谱分析》1992,12(2):105-110
本文对近些年来用电热原子吸收和火焰原子吸收测定镱时,为提高镱的灵敏度而采用的各种方法进行总结评述。 相似文献
37.
Powder samples of the ternary phosphates A3Lu(PO4)2:Yb3+ (A = Na, Rb) have been synthesised by solid state reactions. The spectroscopic properties of Yb3+ in double phosphate host lattices were investigated using absorption, emission and excitation spectra at 4, 10 and 293 K in the VUV to IR range. The results obtained for both types of phosphates are compared. Together with the fundamental 2F5/2 → 2F7/2 emission in the IR range, a broad band emission with two peaks in the UV region were observed in Yb3+‐activated Na3Lu(PO4)2. The second emission is due to a charge–transfer transition type. The influence of the alkali metal cation site of the host lattice on the luminescence properties was investigated. The tentative energy level scheme of the ground and excited 2FJ (J=7/2, 5/2) levels is described. 相似文献
38.
Facile Yb(OTf)3 promoted one-pot synthesis of polyhydroquinoline derivatives through Hantzsch reaction 总被引:1,自引:0,他引:1
Yb(OTf)3 catalyzed efficient Hantzsch reaction via four-component coupling reactions of aldehydes, dimedone, ethyl acetoacetate and ammonium acetate at ambient temperature was described as the preparation of polyhydroquinoline derivatives. The process presented here is operationally simple, environmentally benign and has excellent yield. Furthermore, the catalyst can be recovered conveniently and reused efficiently. 相似文献
39.
M. V. Bogdanovich A. I. Enzhievskii G. I. Ryabtsev V. V. Kuznetsova V. V. Mashko L. L. Teplyashin L. I. Burov A. G. Ryabtsev M. A. Shchemelev A. S. Kraskovskii 《Journal of Applied Spectroscopy》2006,73(4):546-550
Based on analysis of the laser emission spectra of borosilicophosphate glass, coactivated by Er3+ and Yb3+ ions, we have determined the structure of the Stark splitting of the luminescence band for the erbium ion in the 1.5 μm region
(the transition 4I13/2 → 4I15/2). In the wavelength interval 1532–1547 nm, we identified 12 sets of lines belonging to different types of optical centers
of predominantly cubic symmetry.
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Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 4, pp. 483–487, July–August, 2006. 相似文献
40.