铋掺杂近红外发光钽锗酸盐玻璃的基础研究

发布时间：2018-06-04 19:43

本文选题：铋 + 近红外发光　；参考：《华南理工大学》2015年硕士论文

【摘要】：随着信息社会的发展,数据在人类社会中扮演着越来越重要的角色,人们对数据流量的渴求达到了前所未有的程度,高速率和大容量成为光纤通信系统的研究重点。研制超宽带光放大器是实现大容量光纤通信系统的关键,但是,传统的稀土离子掺杂光纤放大器存在难以克服的缺陷,放大带宽比较窄,尽管研究人员做出了很大的努力,稀土离子掺杂光纤放大器放大带宽还是很难超过100 nm。与稀土离子相比,铋元素在玻璃基质中具有1000—1600 nm的超宽带近红外发光,这一范围可以覆盖石英光纤的整个低损耗通信窗口,铋掺杂玻璃材料有望成为新一代超宽带光放大器材料。本论文根据前人对铋掺杂玻璃材料的研究,针对该种材料存在的问题,选择具有较好近红外发光性能的铋掺杂钽锗酸盐玻璃体系进行了系统的研究。研究了熔制时间对铋掺杂钽锗酸盐玻璃的均匀性及近红外发光性能的影响,延长熔制时间虽然可以改善玻璃的均匀性,但是也会造成材料中铋的大量挥发。因此,我们希望通过向玻璃组分中引入碱金属氧化物,降低玻璃的熔制温度及熔制时间,以减少铋的挥发。但是,碱金属氧化物的引入会造成铋掺杂钽锗酸盐玻璃的分相,使玻璃中析出铋金属,另外,碱金属氧化物通过破坏玻璃的网络结构,使铋的近红外发光强度降低。在实验中,我们构建出了碱金属氧化物浓度、玻璃微结构、铋近红外发光性能之间的关系。由于铋对周围基质环境非常敏感,铋的近红外发射峰峰位随着玻璃组分的不同会有很大的变化,我们在实验中建立了铋掺杂钽锗酸盐玻璃近红外发射峰峰位与Ta2O5及Bi2O3浓度的定量关系,使我们能够预测一定玻璃组分中铋的近红外发射峰峰位,这对铋近红外发光玻璃的组分设计具有指导意义。利用实验中制备的不同铋掺杂钽锗酸盐玻璃样品,研究了不同组分玻璃中铋的激发光谱及发射光谱的变化,依据激发光谱和发射光谱数据,探讨了铋的近红外发光机理,发现玻璃中铋的近红外发光来自不同的铋活性中心。考虑到该种材料器件化后的使用环境,探索了高温对铋掺杂钽锗酸盐玻璃近红外发光性能的影响,在不同Ta2O5和Bi2O3浓度的玻璃样品中,近红外发光强度的热衰随着温度降低仍可以恢复,但是随着样品中Li2O浓度的增加,样品近红外发光强度的热衰变得逐渐不可恢复。为了探索铋掺杂钽锗酸盐玻璃利用管棒法制备光纤的可行性,研究了玻璃的热学性能,随着热处理温度升高,玻璃中会先后析出Ta2O5和Ge O2晶体,并且钽锗酸盐玻璃软化温度比较高,希望通过引入Li2O降低玻璃软化点,但是随着Li2O浓度的增加,铋近红外活性中心热稳定性变差,所以铋掺杂近红外发光玻璃中需要谨慎的引入碱金属氧化物。
[Abstract]:With the development of information society, data plays a more and more important role in human society. The demand for data flow has reached an unprecedented degree. High speed and large capacity have become the research focus of optical fiber communication system. The development of ultra-wideband optical amplifier is the key to realize the large capacity optical fiber communication system. However, the traditional rare-earth ion doped fiber amplifier has some disadvantages, such as narrow amplification bandwidth, although researchers have made great efforts. The amplification bandwidth of rare-earth ion doped fiber amplifier is still difficult to exceed 100 nm. Compared with rare earth ions, bismuth has UWB near infrared luminescence of 1000-1600 nm in glass matrix, which can cover the whole low-loss communication window of quartz fiber. Bismuth-doped glass is expected to become a new generation of ultra-wideband optical amplifier materials. In this paper, based on the previous studies on bismuth-doped glass materials, the bismuth doped tantalum germanate glasses with good near infrared luminescence properties were selected to study systematically. The influence of melting time on the homogeneity and near infrared luminescence properties of bismuth doped tantalum germanate glasses was studied. Although prolonging the melting time can improve the homogeneity of the glass, it can also cause a large amount of volatilization of bismuth in the glass. Therefore, we hope to reduce the volatilization of bismuth by introducing alkali metal oxides into the glass components, reducing the melting temperature and melting time of the glass. However, the introduction of alkali metal oxide will lead to the separation of bismuth doped tantalum germanate glass and the precipitation of bismuth metal in the glass. In addition, the alkali metal oxide decreases the near infrared luminescence intensity of bismuth by destroying the network structure of the glass. In the experiment, the relationships among alkali metal oxide concentration, glass microstructures and near infrared luminescence properties of bismuth were obtained. Because bismuth is very sensitive to the surrounding matrix environment, the peak position of near infrared emission of bismuth varies greatly with the glass composition. The quantitative relationship between the peak position of near infrared emission of bismuth doped tantalum germanate glasses and the concentration of Ta2O5 and Bi2O3 has been established, which enables us to predict the near infrared emission peak of bismuth in certain glass components. It is of guiding significance for the composition design of bismuth near infrared luminescent glass. The changes of excitation and emission spectra of bismuth in different bismuth doped tantalum germanate glasses were studied. Based on the data of excitation and emission spectra, the near infrared luminescence mechanism of bismuth was discussed. It is found that the near infrared luminescence of bismuth in glass comes from different bismuth active centers. The effect of high temperature on the near infrared luminescence properties of bismuth doped tantalum germanate glass was investigated in consideration of the application environment of the device. In the glass samples with different Ta2O5 and Bi2O3 concentrations, The thermal decay of NIR luminescence intensity can be recovered with the decrease of temperature, but with the increase of Li2O concentration in the sample, the thermal decay of NIR luminescence intensity becomes gradually unrecoverable. The thermal properties of bismuth doped tantalum germanate glasses were studied in order to explore the feasibility of fabricating optical fibers by tube bar method. With the increase of heat treatment temperature, Ta2O5 and GE O 2 crystals were precipitated successively in the glass. The softening temperature of tantalum germanate glass is relatively high. We hope to reduce the softening point by introducing Li2O, but with the increase of Li2O concentration, the thermal stability of bismuth near infrared active center becomes worse. Therefore, bismuth doped near infrared luminescent glasses need careful introduction of alkali metal oxides.
【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ171.734

【共引文献】