800nm激发下AlF_3基氟化物玻璃中高掺杂Er^(3+)的上转换光谱性质

Upconversion Fluorescence Spectroscopy in AlF_3-Based Fluoride Glass with High Erbium Dopant Level Under 800 nm Excitation

在８００ ｎｍ 激光二极管激发下， 研究高掺杂Ｅｒ３＋ （摩尔比大于３％ ）的ＡｌＦ３ 基（ＡＹＦ、ＡＺＦ）玻璃的红外－可见上转换发光性质。在ＡＹＦ玻璃中， ５５０ ｎｍ 绿光上转换的最佳Ｅｒ３＋ 掺杂摩尔比为６％ ， 而在ＡＺＦ玻璃中为１２％ 。随着Ｅｒ３＋ 掺杂量的增加， 红光与绿光上转换发光强度比（Ｉｒ／Ｉｇ） 增加。这被认为与两个Ｅｒ３＋ 离子（一个在４Ｉ濘濚态、另一个在４Ｓ濐濚态） 的交叉弛豫过程有关。同时由于此交叉弛豫作用， 上转换红光发射强度Ｉ∝Ｐｅｘ１．６。

Infrared to visible frequency upconversion fluorescence spectroscopy in high Er 3+ doped AlF 3 based fluoride glass, excited at 800 nm, is experimentally investigated. In AYF glass, the optimum Er 3+ content for 550 nm emission is about at 6% mol ratio, which is 12% mol ratioin AZF glass. With the increasing of Er 3+ content, the intensity ratios of the red emission to the green emission (I r /I g ) is increased in AYF and AZF glasses, and the red emission intensity in these glasses depends on (P ex ) 1.6 . They are mainly due to a cross relaxation process between two erbium ions, one in the  4S 3/2  and the other in the  4I 9/2 .