With the Si/Al doping quantity increasing, the intensity of the BaO-(l-x)SiO2-*Al2O3-B2O3-0.005Er3+ (x =0,0. 5,1,mole fraction) glass samples show the opposite trend at 1 540 nm infrared emitting and 540 nm up-conversion luminescence. We discuss the internal relation between the rare earth ion's peripheral micro structure and fluorescence behavior. The process of electron transition for up-conversion and infrared emitting are illustrated by the energy diagram. Infrared FTIR transmission spectra show that the maximum phonon energy does not significantly change with the doping concentration. This indicates that the change of spectrum in different concentration is not derived from the influence of the maximum phonon energy. The calculation by Judd-Ofelt theroy shows that the local symmetry around rare earth ions varies with doping quantity of Al3+/Si4+. Radiative decay rates (A) , the radiative lifetime(r) , fluorescence branching ratios (β) , and stimulated emission cross section (a) for 540 nm and 1. 54 μm are calculated. The results show that the changes are opposite. Finally, the fluorescence decaying curves of 4I13/2-4I15/2 for Er3+ in the borate glass samples are characterized, which is consistent with the experimental results.%针对Si/Al掺杂量增大使BaO-(1-x)SiO2 -xAl2O3-B2o3-0.005Er3+(x=0,0.5,1,摩尔分数)玻璃样品的1540 nm红外发光和540 nm上转换发光强度呈现相反的变化趋势,讨论了阳离子掺杂对稀土离子周边对称性和电负性变化与荧光行为的内在关系.红外傅里叶透射光谱显示,不同掺杂浓度下样品的最大声子能量没有明显变化,说明光谱随掺杂浓度的变化与玻璃体系的最大声子能量无关.根据Judd-Ofelt理论计算了4I13/2和4S3/2能级的光学参数,通过比较两能级的跃迁几率(4)、寿命(τ)、荧光分支比(β)和受激发射截面(σ)等光学参数,发现4I13/2能级和4S3/2能级的相关参数呈现相反的趋势.最后测试了样品4I13/2能级下1540 nm的寿命,进一步从电负性角度考虑了样品的发光效率.理论计算和实验结果相符.
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