制备了适用于钾钠离子交换波导的Tm3+/Yb3+掺杂铝锗酸盐玻璃, 利用积分球配以光纤光谱仪在975 nm激光泵浦下对玻璃的上转换荧光进行测试, 解析出样品的绝对荧光特征参量。测试与计算结果显示, 在380 ℃的KNO3熔盐中, Tm3+/Yb3+掺杂的铝锗酸盐玻璃的钾钠离子交换有效扩散系数为0.070 μm2/min, 热离子交换过程易于控制。铝锗酸盐玻璃样品中, Tm3+主要发出477 nm蓝光和806 nm近红外光, 其中近红外光为支配性发射。绝对荧光参数和激发功率密度呈正相关, 当功率密度达到1 482 W/cm2时, 三光子上转换蓝光的绝对光谱功率、净发射光子数和量子产率分别为269 μW、6.46×1014/s和1.43×10-4, 双光子近红外光上转换对应的3个参量分别为4 024 μW、1.63×1016/s和3.61×10-3。基于波导适用型铝锗酸盐玻璃中Tm3+上转换荧光的绝对化表征, 为进一步研发光电子器件和激光材料提供了有益的数据参考。

Tm3+/Yb3+ doped aluminum germanate glasses adapting for K+-Na+ ion-exchanged waveguide were fabricated. Absolute characteristic parameters for upconversion (UC) fluorescence of glass samples were measured by integrating sphere coupled with fiber optic spectrometer under the excitation of 975 nm pump laser. The measurement and calculation results show that the effective diffusion coefficient of K+-Na+ thermal ion-exchange is 0.070 μm2/min when Tm3+/Yb3+ doped aluminum germanate glasses are immersed in KNO3 molten salt at 380 ℃, indicating that the K+-Na+ ion-exchange process is controllable. Tm3+ in aluminum germanate glasses emits 477 nm blue and 806 nm near-infrared (NIR) fluorescence, and the NIR emission plays a dominant role. The absolute fluorescence parameter is identified as a positive correlation with laser power density. When the power density is 1 482 W/cm2, the emission spectral power, emission photon and quantum yield for blue three-photon UC fluorescence are 269 μW, 6.46×1014/s and 1.43×10-4, and the ones for NIR two-photon UC fluorescence are 4 024 μW, 1.63×1016/s and 3.61×10-3, respectively. The absolute characterization for UC fluorescence of Tm3+ in waveguide-typed aluminum germanate glasses provides a valuable reference in developing photoelectronic devices and laser materials.