We report an Er3t-doped fluorogallate glass with good thermal and chemical stability. The low maximum phonon energy and high mid-infrared(IR) transmittance of the glass are confirmed by Raman and IR spectra,respectively. Based on Judd–Ofelt theory, intensity parameters and radiative properties are determined from the absorption and emission spectra. The proposed glass possesses a large fluorescence branching ratio β(21.71%) and a maximum stimulated emission cross-section σemof Er3t:4I11∕2→4I13∕2transition at 2.71 μm(1.04 × 10-20cm2). The results indicate that it can be potentially applied in high-power 2.7 μm fiber lasers.
为了提高调节脉冲氙灯的效率,研究了脉冲氙灯电流峰值与电容初始电压之间的关系,并在此基础上量化分析了脉冲氙灯参数对电流峰值的影响。实验分组分别测量了具有不同充气气压、电极间距以及灯管内径等参数的脉冲氙灯工作在不同电容初始电压条件下的电流峰值。实验发现,电容初始电压在1.75-4.25 k V范围内,电流峰值与电容充电电压有着良好的线性关系。对此进行了线性函数模拟,得到模拟结果与实验测量结果的相对误差〈5%。通过计算分析充气气压、电极间距以及内径等条件与模拟线性函数斜率的关系,验证了所得结果的正确性以及研究方法的合理性,为脉冲氙灯电流峰值的研究提供了一种新的方法。同时发现灯管内径对脉冲氙灯电流峰值影响十分强烈,充气气压对电流峰值影响相对较弱。这些现象对于新型脉冲氙灯的研制、选用及调试都有参考意义。
Emission enhancement at 2.7 μm is observed in Er^(3+)/Pr^(3+)-codoped germanate glasses when pumped by a 980-nm laser diode.Significant reductions in 1.5-μm emission and upconversion intensity indicate efficient energy transfer between Er^(3+) and Pr^(3+);the energy transfer efficiency is as high as 77.4%.The mechanisms of energy transfer are discussed in detail.The calculated emission cross-section of Er^(3+)/Pr^(3+)-codoped germanate glass is 8.44×10^(-21) cm^2,which suggests that Er^(3+)/Pr^(3+)-codoped germanate glass can be used to achieve efficient 2.7-μm emission.
