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81.
Carsten Thirstrup Yuan Shi Per B kkelund Bera P alsd ttir 《Fiber and Integrated Optics》1996,15(1):1-6
Modulation of the absorption and refractive index in Er3+-doped fibers for a signal wavelength in the 1550-nm band and a pump wavelength of 980 nm is investigated. The experimental results are compared with a model that takes into account optical transitions between the ground state and the metastable state in Er3+. Good agreement between the experiment and the model is obtained apart from a wavelength-independent constant in the refractive index modulation, which is discussed. 相似文献
82.
S.W. Harun H.A. Abdul-Rashid S.Z. Muhd-Yassin M.K. Abd-Rahman K.K. Jayapalan H. Ahmad 《Optics & Laser Technology》2008,40(1):88-91
An efficient erbium–ytterbium-doped fiber amplifier (EYDFA) is demonstrated by forward and backward pumping a 3 m erbium/ytterbium co-doped fibers (EYDF) in single- and double-pass configurations using a 20 mW pump. At the input signal wavelength of 1536 nm, the forward- and backward-pumped double-pass amplifiers achieved a maximum low-signal gain of 37.2 and 28.6 dB and a corresponding noise figure of 5.4 and 10.8 dB, respectively. Whereas, the forward- and backward-pumped single-pass amplifiers (at the same wavelength) achieved a maximum low-signal gain of 20.0 and 22.2 dB and a corresponding noise figure of 4.6 and 10.3 dB, respectively. The double-pass design offers an economical solution to high-efficiency and high-gain optical amplifiers. 相似文献
83.
首次实验观察到在1064nm激光泵浦下掺Er~(3+)石英光纤中的共振增强受激四光子混频现象和光学自由感应衰减过程.在频域和时域上实验证明了Er~(3+)的~4I_(11/2)激发态能级对受激四光子混频产生的反斯托克斯谱线的增强效应. 相似文献
84.
The comprehensive analysis about heat-generating processes is presented in Er:tellutire glass. The heat fraction of each process and total heat fraction during pumping are investigated. The results show that upconversion is an important heat-generation process and heat problem is serious especially at high Er3+ doping level. The influence of pump power on heat fraction is also discussed. Based on the heat analysis, the optimized doping concentration range of Erbium ions is about 0.5 mol% to 1.0 mol%. 相似文献
85.
加注稀土元素铒改善轴承表面性能的研究 总被引:2,自引:0,他引:2
在Mo^++N^+注入模式的基础上,应用电子能谱、卢瑟福背散射谱、扫描电子显微镜和MHK-500型摩擦磨损试验机等研究了加注稀土元素铒正离子Er^+对轴承表面摩擦学性能和耐蚀性能的影响。结果表明,在合理配置Mo^+、N^+、Er^+之能量和剂量的情况下,加注Er^+既能更好地改善轴承的表面性能,又能使重离子的强韧化效果提高2-4倍以上,表明MO^++N^++Er^+注入模式是一种具有良好应用前景的 相似文献
86.
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
87.
掺铒硅的发光特性及机理 总被引:3,自引:0,他引:3
Si中掺Er是利用Er离子的发光来制造Si基发光二极管的一条途径,文章对掺Er的一些基本物理特性,如铒在硅中的电子结构,电学特性以及光致发光和电致发光的机理等,根据目前研究的进展进行了综合介绍。 相似文献
88.
Xiu-li Yan Xing Wu Jian-fei Zhou Zhi-guo Zhang Jinguo Wang 《Journal of Crystal Growth》2000,220(4):543-547
High optical quality Er3+:YVO4 laser crystals have been grown by using the floating zone method (FZ). The spectroscopic properties and 3 μm lasing of Er3+:YVO4 were investigated. It is found that the Er3+ concentration has a negative effect on the emission of the transition 4I13/2→4I15/2(1.55 μm ), and a positive effect on that of the 4I11/2→4I13/2 transition (2.68 μm). With direct upper-state pumping and a plane-concave cavity a self-terminating laser was achieved at the wavelength of 2.724 μm in the 30 at% Er3+ doped sample. 相似文献
89.
The general formalism for polarization observables in elastic electron deuteron scattering is extended to incorporate parity-
and time-reversal-violating contributions. Parity-violating effects arise from the interference of γ and Z exchange as well as from the hadronic sector via a small parity-violating component in the deuteron. In addition we have
allowed for time-reversal-invariance-violating contributions in the hadronic sector. Formal expressions for the additional
structure functions are derived, and their decomposition into the various multipole contributions are given explicitly.
Received: 19 December 2000 / Accepted: 14 February 2001 相似文献
90.
A series of In:Yb:Er:LiNbO3 crystals have been grown. The UV‐Vis absorption spectra and Infrared (IR) transmission spectra were measured and discussed in terms of the spectroscopic characterizations and the defect structure of the In:Yb:Er:LiNbO3 crystals. The optical damage resistance was characterized by the transmitted beam pattern distortion method. The optical damage resistance of In (3.0mol %):Yb:Er:LiNbO3 crystal is one order of magnitude higher than that of other crystal. The dependence of the optical damage resistance on the defect structure was studied. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献