ZBLAN玻璃中Pr^(3+)掺杂离子~3P_0和~1D_2能级的发光特性和寿命

Fluorescent Properties and Lifetimes of ~3P_0 and ~1D_2 Levels in Pr^(3+)∶ZBLAN Glass

对ZBLAN氟锆酸盐玻璃中Pr3+掺杂离子 3P0 和 1D2 能级的寿命和发光特性进行了较详细的光谱学研究。首先测量了两种掺杂浓度 (质量分数分别为 1×10-3, 5×10-3 )的Pr3+∶ZBLAN玻璃的吸收光谱,然后运用时间分辨激光光谱技术测量了 3P0 和 1D2 能级在激光单光子共振激发下的荧光发射谱和能级寿命。将不同荧光发射谱带的强度和文献报道的Judd Ofelt理论计算辐射跃迁几率数值做了比较分析,证明了文献中理论计算结果的可靠性。由于浓度猝灭效应,在相同的激发条件下,掺杂浓度为 1×10-3样品的荧光发射强度明显大于 5×10-3样品的荧光发射强度。但是从我们的测量结果看,掺杂浓度对 3P0 和 1D2 的能级寿命值无显著影响。掺杂浓度为 1×10-3时,Pr3+离子 3P0 和 1D2 能级的寿命值分别为 46, 322μs。

Heavy-metal fluoride glasses have attracted much attention as host materials due to smaller multi-phonon relaxation rate and high transparence. The optical properties of Pr^(3+) ion doped in hosts have also been investigated extensively for its potential application on full-color displays, optical data storage and biomedical instruments. Since detailed spectroscopic studies provide information leading to an assessment of the application of Pr^(3+) ions, it is very urgent to explore the optical properties of different levels of Pr^(3+) ions in different host materials. The purpose of this paper is to investigate optical characteristics of the ()~3P_0 and ()~1D_2 levels in Pr^(3+)∶ZBLAN fluoride glass. Firstly the absorption spectra of Pr^(3+)∶ZBLAN with two concentrations (1×10^(-3) and 5×10^(-3) in mass fraction) were measured by using a spectrophotometer. Then by using time-resolved laser spectroscopy technique, the fluorescence spectra and the lifetimes of the ()~3P_0 and ()~1D_2 excited states of Pr^(3+) (ions) were investigated under one-photon resonant excitation by a laser beam from the optical parameter oscillator and amplifier system. Experimental fluorescence intensities of the different emission bands were compared with the calculated radiative rates by the Judd-Ofelt theory in literature which indicating that the phenomenological intensity parameters for the Judd-Ofelt theory obtained for Pr^(3+)∶ZBLAN is reliable. Due to the concentration quenching, the fluorescent intensity of the 1×10^(-3) sample is stronger than that of the 5×10^(-3) sample. However, the lifetimes of the ()~3P_0 and ()~1D_2 excited states of Pr^(3+) ions in ZBLAN glass are not influenced by the concentration. For 1×10^(-3) sample, the measured lifetimes of the ()~3P_0 and ()~1D_2 (levels) are 46 and 322 μs, respectively.