【作者】 熊大元；

【导师】 刘煜炎；

【作者基本信息】 华东师范大学 ， 光学， 2004， 硕士

【摘要】 九十年代以来研制出以稀土掺杂的卤化物玻璃为材料的高增益光纤光放大器，后又陆续发现在卤化物及混合卤氧化物玻璃中具有更高的量子效率，但这类卤化物玻璃比较容易吸湿，化学稳定性、机械强度和拉纤性均不好，与信号传输石英光纤难以熔接。利用氧化硅多孔玻璃来组装掺稀土卤化物纳米基团形成复合玻璃材料，以此结合卤化物玻璃和氧化硅玻璃的某些重要优点（量子效率和机械强度高，化学稳定性和可拉纤性好等），使氟玻璃（或卤氧化物玻璃）为稀土离子提供优良的发光环境，同时纳米基团受到氧化硅多孔玻璃的保护和支撑，为工程实用化光放大器件以及新型发光器件奠定材料基础。 工艺上采用改进的钠硼硅酸盐玻璃分相-酸浸蚀法制备了孔径为20-30nm的多孔玻璃，并成功实现了与掺Er³⁺／Yb³⁺的氟玻璃以及掺Eu³⁺离子的氯氧化物的精细复合。对Er³⁺离子单掺和Er³⁺／Yb³⁺双掺的氟玻璃及复合玻璃材料进行了光谱测量和比较分析。发现复合玻璃与相应的氟玻璃中Er³⁺离子相比，上转换光谱发生了显著变化并对其发光机制做了初步解释，提出了有关机理的理论问题。如何从成分设计和工艺方面上减少氟化物对纳米多孔玻璃的腐蚀是实验成功的关键，本文在此方面做了一定深度的探索。 本文还研究了纳米多孔玻璃中的掺Eu³⁺离子的氯氧化物—YOCl固体粉末和EuCl₃溶液的光谱性质。与普通的YOCl荧光粉末相比，纳米基YOCl：Eu³⁺粉末中Eu³⁺的电偶极跃迁⁵D₁→⁷F₂的发射光谱被展宽，同时蓝移7nm；Eu³⁺的⁵D₀→^F₁跃迁与⁵D₀→⁷F₂跃迁的相对强度之比在两种激发波长（254nm及393nm）下均得以增大。与普通的EuCl₃的溶液相比，纳米基溶液不具有典型的小尺寸效应及量子限域效应，但Eu³⁺高能级的激发态引起的发光得以增强。由于这种复合方法同时吸收了纳米多孔玻璃形状一定、机械强度高等优点，这种复合材料有望发展成为一种新型实用光学材料。更多还原

【Abstract】 Since the ninetieth decade last century, efforts have been made to develop rare earth (RE) doped non-oxide glasses into light amplifying materials. Rare earth ions doped halides and mixed halides with higher quantum efficiencies had also been discovered. Nevertheless, there had been concerns that these halide and mixed halide light amplifying materials were fragile, sensitive to moisture, and not suitable for being welded with the widely used quartz fibers. These intrinsic drawbacks have prevented the RE doped non-oxide glasses from engineering applications as optical amplifying materials and luminescent materials. In this paper we took advantage of nanoporous silica glass to develop the optical composite material that was nanoscale fluoride glass granules embedded in silica glass. The network of the non-oxides glass is interwoven with the network of silica glass. This material combines the advantage of non-oxides glass as a good optical amplifying substrate with that of silica glass as a good protector and holder. In addition, a gradient concentration of the non-oxides in silica glass along one dimension may allow for almost pure silica glass at two ends of the material, which would lead in turn to the welding ability of the material with quartz fibers.The nanoporous glass was prepared using an improved method of phase separation and acid eroding of sodium borosilicate glass. The spacing between the skeletons and the thickness of the skeleton are both 20-30nm in average. The melt of Er3+/Yb3+ doped fluoride glass was irrigated into the porous glass to make a new composite material. Up-conversion spectrum of the composite material was observed, which was different from that of the bulk Er3+/Yb3+ doped fluoride glass. Some related mechanism was also put forwarded. Success of the impregnation process was based on the elimination of water and hydroxyl and the control of etching.Luminescent properties of YOCl:Eu3+ powders and EuCls solution embedded in nanoporous glass were also investigated. In comparison with those in the normal micro-powder phosphor, emission spectra of Eu3+ in nano-YOCl:Eu3+ became much broader. Blueshift(7nm) was observed in the lines due to 5D0→ 7F2 transition and Eu-O charge transfer excitation band. The ratio intensities of the 5D0→ 7F1 transition to the 5D0→7F2 transition of Eu3+ became larger and changed at different excitation wavelengths(254nm and 393nm). In comparison with those in the bulk EuCl3 solution, nano- EuCl3 solution had neither small size effects nor quantum confinement effects. Luminescence due to upper levels of Eu3+ in the nano-solution was enhanced. This approach also combines the advantages of nanoporous glass in offering good chemical shielding and mechanical support. The results obtained indicate that this approach likely may make a new kind of luminescent material.更多还原