In this paper, we reported the spectroscopic properties of praseodymium ions (Pr3+) doped transparent oxyfluoride glass ceramic excited with different laser lines, such as 532, 514.5 and 476.5 nm. and the spectroscopic features of Pr3+ ions in LaF3 nanocrystals (NCs) and in oxide glass were presented. It was found that the population on 3P0 state of Pr3+ ion in NCs and in glass can be achieved by multi-phonon assistance process when excited by 514.5 nm laser lines. As a comparison, 476.5 nm laser line which is mainly resonant with the 3H4 to 3P0 transition of Pr3+ ions in NCs is used as the excitation source, transitions from 3P0 state to many lower states, such as 3H5, 3H6, 3F2 manifolds were observed and it showed significant difference from those excited by 532 nm and 514.5 nm laser lines in which only transition from 3P0 to 3H5 exists. We attribute those different spectroscopic features as selectively excitation of Pr3+ ions in different environments where exist strong/weak electron-phonon coupling in the 3P0,1 states of Pr3+ ion in NCs and in glass. Crystallization behavior and vibrational properties of transparent glass ceramic were also stu-died by Raman spectroscopy excited by 532 nm and 514.5 nm laser lines.%用不同的激发波长532,514.5,476.5 nm,研究稀土Pr3+ 掺杂的透明氟氧化物玻璃陶瓷中Pr3+ 在LaF3 微晶环境和玻璃环境中的不同的荧光行为.对于微晶中的Pr3+ 离子,当用532 nm 和514.5 nm激发玻璃陶瓷时,观察到从3P0 能级到3H5 能级的发射,和1D2 能级到基态3H4能级,3P0 能级到3H6 能级的发射.我们认为微晶中Pr3+ 离子的3P0 能级上的电子布局是依靠电声子耦合-多声子辅助来实现的.为了进行比较,用476.5 nm 共振激发玻璃及微晶中Pr3+ 离子的3P0 能级,观察到3P0 能级到很多低能级如:3H5、 3H6、3F2的跃迁.而当在532 nm 和514.5 nm 非选择激发时,只有 3P0 能级到3H5 能级的发射存在.我们认为这是由于不同的激光波长选择激发了不同环境中的Pr3+ 离子,532 nm 和514.5 nm 激发线选择激发了电声子耦合环境强中Pr3+ 离子.不同Pr3+ 离子掺杂摩尔分数分别为0.005%,0.05%,0.5%的发射光谱的研究还表明,这些电声子耦合环境强中的Pr3+ 离子浓度很高,很容易发生浓度猝灭现象.最后,用拉曼光谱研究了这类玻璃陶瓷的结晶性为和振动特性.
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