掺稀土锗酸盐玻璃的中红外光谱性能研究

发布时间：2018-06-21 03:51

本文选题：稀土离子 + 能量转移　；参考：《中国计量学院》2015年硕士论文

【摘要】：~3μm波长的中红外荧光发射包含了许多大气分子的特征谱线带,在军事对抗、医疗手术、环境污染检测以及光通信等领域有重要应用。本论文主要目的在于研究能够适用于~3μm激光输出的玻璃材料。通过对玻璃基质的组分调整及稀土离子的浓度优化,制备出了适用于~3μm发光的玻璃材料。本文首先制备了不同Ga2O3含量的锗酸盐玻璃,对玻璃样品进行了XRD分析。发现当Ga2O3含量达到25 mol%时,玻璃开始变得不透明。对未析晶样品进行了热分析、发现所制备的样品具有较高的ΔT和kgl(140°C和0.176)。进一步研究了玻璃的结构、物理及光学性能,通过拉曼光谱分析发现玻璃的最大声子振动频率随着Ga2O3含量的增加逐渐向低波数方向移动。测试了Er3+的吸收光谱,讨论了J-O参数及辐射性质。研究了玻璃的红外透过光谱,发现样品的最大透过率高达84%。中红外荧光光谱表明2.7μm发射强度随着Ga2O3含量增加先降低后增加。计算发现所制备样品的最大发射截面可达4.68×10-21 cm2。利用速率方程和Inokuti-Hirayama模型计算了能量转移参数及能量转移上转换系数,解释了2.7μm荧光行为。在前一章研究的基础上,进一步制备了R2O3(R=Al/Y/Gd/La)及Nb2O5改进的锗酸盐玻璃。研究了R2O3对玻璃密度、折射率等物化参数的影响,比较了R2O3及Nb2O5对其热稳定性、析晶活化能等热力学性能。发现Y2O3改进的玻璃具有更高的ΔT及kgl值(175°C和0.224)。研究了样品的拉曼光谱,对其玻璃结构及最大声子能量进行了分析。中红外荧光光谱分析表明Y2O3改进的锗酸盐玻璃在2.7μm处具有较高的荧光强度及发射截面。研究了Er3+的能量转移过程,讨论了2.7μm荧光增强的机理。采用Y2O3改进的锗酸盐玻璃为基质,研究了Er3+浓度对其2.7μm荧光性能的影响,发现所制备的样品能实现6 mol%Er3+的高浓度掺杂而没有荧光猝灭。基于上转换及近红外荧光光谱,提出了合理的能量转移机理。研究发现激发态吸收(ESA2)、交叉弛豫(CR)及能量转移上转换(ETU2)过程随着Er3+浓度的增加而变强。这些过程均有利于提高激光上下能级的粒子数反转,增强2.7μm荧光发射。制备了Er3+/Tm3+共掺锗酸盐玻璃,发现Tm3+能够有效的敏化Er3+粒子,显著增强了2.7μm发射。讨论了Tm3+与Er3+间的能量转移机理并计算了Tm3+与Er3+间的能量转移微观参数及能量转移效率。结果表明Er3+:4I13/2→Tm3+:3F4的能量转移系数(2.94×10-39cm6/s)远大于Er3+:4I11/2→Tm3+:3H5的值(0.93×10-40 cm6/s)。通过速率方程分析,进一步证实了2.7μm,1.8及1.53μm荧光变化。制备了Er3+-Yb3+共掺锗酸盐玻璃,在980nm波长泵浦下,Er3+-Yb3+共掺样品的2.7μm、1.53μm及上转换发射强度明显高于Er3+单掺样品。随着Yb3+浓度的增加,其发射强度单调增加,没有出现明显的荧光猝灭现象。接着讨论了Er3+与Yb3+的能量转移机理,Yb3+:2F5/2→Er3+:4I11/2的能量转移微观参数高达1.42×10-39 cm6/s。本文最后研究了Ho3+/Yb3+共掺锗酸盐玻璃的2.9μm光谱性能。基于吸收光谱及J-O理论,计算了Ho3+的Judd-Ofelt强度参数及辐射性质,发现Ho3+:5I6→5I7跃迁(2.9μm)的自发辐射跃迁几率高达36.66 s-1。中红外荧光光谱表明当Ho3+:Yb3+的浓度比为0.1:2时,2.9μm荧光最强。计算的2.9μm发射截面高达8.58×10-21 cm2,当反转粒子数P为0.5时,在2866-3000nm处的增益为正。通过上转换、近红外及中红外光谱分析,讨论了Ho3+和Yb3+的能量转移机理,计算了Yb3+到Ho3+的能量传递效率及能量传递系数,分别为35.8%和4.06×10-40 cm6/s。最后利用YokotaTanimoto模型计算了不同Ho3+浓度的Yb3+到Ho3+的能量转移系数,发现随着Ho3+浓度的增加,其值逐渐减小,这表明5I6能级的粒子数随着Ho3+浓度而降低,与实验结果一致。
[Abstract]:The middle infrared fluorescence emission of ~3 mu m wavelength contains many characteristic spectral lines of atmospheric molecules. It has important applications in military confrontation, medical operation, environmental pollution detection and optical communication. The main purpose of this paper is to study glass materials that can be applied to the output of ~3 mu m laser. The glass material suitable for ~3 mu m luminescence was prepared. The germanate glass with different Ga2O3 content was prepared in this paper. The glass samples were analyzed by XRD. It was found that when the content of Ga2O3 reached 25 mol%, the glass began to become opaque. The structure, physical and optical properties of the glass are further studied. The vibration frequency of the maximum phonon of the glass is gradually moved to the low wave number with the increase of the Ga2O3 content. The absorption spectra of Er3+ are tested and the J-O parameters and radiation properties are discussed. The infrared transmittance of the glass is studied. The infrared transmittance of the glass is studied. It is found that the maximum transmittance of the sample up to 84%. mid infrared fluorescence spectra shows that the emission intensity of 2.7 mu m decreases first and then increases with the increase of Ga2O3 content. The maximum emission cross section of the prepared sample can reach 4.68 x 10-21 cm2. utilization rate equation and Inokuti-Hirayama model to calculate the energy transfer parameters and the energy transfer upconversion system The fluorescence behavior of 2.7 mu m was explained. On the basis of the previous chapter, R2O3 (R=Al/Y/Gd/La) and Nb2O5 improved germanate glass were further prepared. The effects of R2O3 on the physical parameters of glass density, refractive index and so on were studied. The thermodynamic properties of R2O3 and Nb2O5 on its thermal stability and crystallization activation energy were compared. The improved glass tool with Y2O3 was found. A higher Delta T and KGL value (175 degree C and 0.224). The Raman spectra of the samples were studied, and the glass structure and the maximum phonon energy were analyzed. The mid infrared fluorescence spectrum analysis showed that the Y2O3 improved germanate glass had high fluorescence intensity and the emission cross section at 2.7 mu m. The energy transfer process of Er3+ was studied, and 2.7 mu m fluorescence was discussed. Strengthening mechanism. Using Y2O3 improved germanate glass as matrix, the effect of Er3+ concentration on its 2.7 u m fluorescence is studied. It is found that the prepared samples can achieve high concentration of 6 mol%Er3+ without fluorescence quenching. Based on upconversion and near infrared fluorescence spectroscopy, the mechanism of energy transfer is proposed. ESA2, cross relaxation (CR) and energy transfer up conversion (ETU2) process become stronger with the increase of Er3+ concentration. These processes are beneficial to increase the number reversal of the particles in the upper and lower energy levels of the laser and enhance the fluorescence emission of 2.7 mu m. The Er3+/Tm3+ Co doped germanate glass is prepared, and it is found that Tm3+ can sensitize Er3+ particles effectively and significantly enhance the emission of 2.7 u m. The energy transfer mechanism between Tm3+ and Er3+ is discussed and the energy transfer micro parameters and energy transfer efficiency between Tm3+ and Er3+ are calculated. The results show that the energy transfer coefficient (2.94 x 10-39cm6/s) of Er3+: 4I13/2 to Tm3+ is far greater than Er3+: 4I11/2 > Tm3+: (0.93 x 10-40). Through the rate equation analysis, further confirmed 2.7 micron, Er3+-Yb3+ Co doped germanate glass was prepared by 1.8 and 1.53 m fluorescence. Under 980nm wavelength, 2.7 mu m, 1.53 mu m and upconversion emission intensity were significantly higher than those of Er3+ single doped samples. With the increase of Yb3+ concentration, the emission intensity of the samples increased monotonically, and no obvious fluorescence quenching was found. Then Er3+ and Yb were discussed. The energy transfer mechanism of 3+, Yb3+: 2F5/2 to Er3+: the micro parameters of energy transfer of 4I11/2 are as high as 1.42 x 10-39 cm6/s.. Finally, the spectral properties of 2.9 mu m of Ho3+/Yb3+ Co doped germanate glass are studied. Based on the absorption spectrum and J-O theory, the Judd-Ofelt intensity parameters and radiating properties of Ho3+ are calculated, and Ho3+: Ho3+: 2.9 micron transition (2.9 mu) self is found. The radiation transition probability up to 36.66 s-1. in the infrared fluorescence spectrum shows that when the concentration ratio of Ho3+: Yb3+ is 0.1:2, the fluorescence of 2.9 mu m is the strongest. The calculated 2.9 mu m emission cross section is up to 8.58 x 10-21 cm2, and the gain at 2866-3000nm is positive when the number P of the reverse is P. The Ho3+ and Yb3 are discussed by upconversion, near infrared and mid infrared spectroscopy. The energy transfer mechanism of + + is calculated. The energy transfer efficiency and energy transfer coefficient of Yb3+ to Ho3+ are calculated, 35.8% and 4.06 x 10-40 cm6/s. respectively. Finally, the energy transfer coefficient of Yb3+ to Ho3+ with different Ho3+ concentrations is calculated by YokotaTanimoto model. It is found that with the increase of Ho3+ concentration, the value gradually decreases, which indicates that the number of particles at the 5I6 level is dependent on the number of Ho3+. The decrease of Ho3+ concentration is consistent with the experimental results.
【学位授予单位】：中国计量学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ171.112

【相似文献】