【作者】 李建勇；

【导师】 宋昌烈；

【作者基本信息】 大连理工大学 ， 光学工程， 2006， 硕士

【摘要】 用中频磁控溅射方法（MFS）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。优化了实验参数,扫描电镜（SEM）和电子探针（EPMA）显示了优化后的效果。室温下测量了薄膜在1.430μm-1.630μm波段范围内光致发光光谱。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0.33at%,Yb∶Er=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Guass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Guass形状变化。另外利用微波电子回旋共振等离子体法（ECR-MW）制备了镱铒共掺Al₂O₃薄膜,研究了其发光特性。 首次利用中频磁控溅射制备成功了非均匀镱铒共掺Al₂O₃光波导放大器薄膜。改变MFS系统双靶的孪生状态是实现非均匀掺杂的关键。对应于掺铒1.67at%,镱12.00at%样品,改变样品台与靶台之间的垂直距离,三条光致发光光谱峰值强度曲线被给出,其中,距离为3.4cm的曲线保持很好的一致性。另外,保持掺镱浓度不变,我们还制备了另外两种掺铒浓度的实验样品。利用激光退火的局部改善功能可以实现更多的非均匀掺杂。 介绍了光纤与波导耦合的多种方法,包括平面波导（PLC）全自动对准与封装系统;优化设计了四种弯曲光波导放大器,利用BCl₃干法刻蚀波导放大器,对光刻试样进行了表征;然后对测量光波导放大器增益进行了准备。 对掺铒、镱铒共掺硅酸盐玻璃的1.54μm荧光寿命进行了测量。实验结果表明荧光衰减曲线是一条单指数曲线,荧光寿命数量级为ms量级;荧光寿命随着样品掺铒浓度的增加呈现减小趋势,而在掺铒浓度一定的情况下随掺镱浓度的变化不明显,主要由于受激发的铒离子把能量通过间接耦合给了猝灭中心;在所考虑的泵浦功率范围内,两种样品的荧光寿命基本不随功率的变化而变化。同时对掺铒0.5at%,镱3.0at%的样品进行了合作上转换发光的实验研究。三条中心波长525nm、543nm和660nm的发光谱在室温下被观测到,对应着铒²H_11/2→⁴I_15/2,⁴S_3/2→⁴I_15/2和⁴F_9/2→⁴I_15/2能级跃迁,上转换机制和能量依赖性被给出。红光和绿光对能量的两次平方依赖性表明了双光子过程的发生。更多还原

【Abstract】 The five series for the Yb/Er co-doped Al₂O₃ films with constant Er concentration have been prepared, on the SiO₂/Si wafer, by medium frequency magnetron sputtering （MFS）. The experimental parameters are optimized, and the results analyzed by SEM and EPMA show the superiorities. The photoluminescence （PL） of the thin films between 1.430μm and 1.630μm are investigated at room temperature. Experimental results show, Ytterbium co-doping efficiently increases the PL peak intensity, and the PL intensity of optimal concentration for 1.00at% Er and Yb:Er ratio of 10:1 enhance by a factor of about 40, compared with that of 1.00at% Er doped film;there exists the optimal Yb/Er ratio with constant Er concentration, this mainly is an interacting result of energy transfer and back energy transfer between Yb and Er, whereas the optimal Yb/Er ratio decrease with increasing the Er concentration;the change trend of PL peak intensity for only Eroped film is similar with Guass figure whereas that for Yb/Er co-doped film is similar with anti-Guass figure as a function of Er concentration. In addition, the Yb/Er co-doped Al₂O₃ films are prepared by microwave electron resonance plasma source （ECR-MW） and the PL of it are investigated.The non-uniform Yb/Er co-doped Al₂O₃ films have been originally prepared by medium frequency magnetron sputtering. The two different targets of this system are critical to realize non-uniform doping. By changing the distance between sample table and targets, three different change curves of photoluminescence peak intensity are presented, and the change curve of distance for 3.4cm keeps good consistency, for the sample of Er 1.67at% and Yb 12.00at%. In addition, the non-uniform films of another two Er concentrations with constant Yb concentration are discussed. By combing the non-uniform doped originality and laser annealing process, more non-uniform doped designs can be realized.Many methods of the couple between the fiber and EDWA are introduced, including Plannar Lightwave Circuit （PLC） alignment system. The four folded designs of EDWA are presented optimally, and the samples are achieved by BC13 ions and investigated. Then, we prepare the gain measurement of those EDWAs.1.54μm fluorescence lifetimes of Er doped and Yb/Er co-doped silicate glasses are measured. Experiments show: the kinetics of luminescence delay is well described by an exponential function with a single time constant, lifetime is on the order of ms;fluorescence lifetime of samples decrease with concentration of only Er doped but change inconspicuouslywith concentration of Yb under constant Er concentration, meanly as energy of excited Er is coupled to quenching site by indirect couple;the lifetime of two samples is independent of power in the range under study. For the samples of Er 0.5at% and Yb 3.0at%, frequency upconversion fluorescence emissions are experimentally investigated. Visible emissions centered at 525nm, 543nm, and 660nm, corresponding to 2Hnn^<sup>* lisa, S3/2^*4Ii5/2, and 4F9/2"^-4Ii5/2 transitions of Er ions, respectively, are simultaneously observed in Yb/Er co-doped silicate glass at room temperature. The upconversion mechanisms and power dependence are presented. The quadratic dependences of the green and red emissions on excitation power reveal that biphotonic processes occur.更多还原