稀土离子掺杂的AlF_3基氟化物玻璃

RARE EARTH DOPED AlF_3-BASED FLOURIDE GLASS

在 8 0 0和 970nmLD激发下 ,分别研究了Er3 +单掺和Yb3 +,Tm3+共掺的AlF3 基 (AYF ,AZF)玻璃中上转换发光、能量传递和浓度猝灭 .在Er3 +掺杂的AlF3 基玻璃 ,随着Er3+掺杂量的增加 ,红光与绿光上转换发光强度比(Ired/Igreen)增加 ,这被认为与两个Er3 +离子 (一个在4 I9/2 态、另一个在4 S3/2 态 )的交叉弛豫过程有关 .在Tm3 + Yb3 +共掺的AlF3 基玻璃中 ,发现对于Tm3 +的浓度猝灭 ,蓝光跃迁比近红外荧光跃迁表现更明显 ,研究还发现Yb3+ Tm3 +共掺AYF和AZF玻璃存在Yb3 +离子对上转换发光的猝灭现象 ,这被认为可能是Tm3+(3F4 )→Yb(3F5/2 )

Energy transfers and upconversion fluorescence spectroscopy in both Er 3+ singly doped and Tm 3+ \|Yb 3+ co\|doped AlF\-3\|based flouride glass,excited at 970?nm,are investigated experimentally.In Er 3+ :AYF glass,the optium Er 3+ content for 550?nm emission is about at 6?mol%,which is 12?mol% in AZF glass.With the increase of Er 3+ content,the intensity ratio of the red emission to the green emission ( I red / I green ) is increased in AYF and AZF glass,and the red emission intensity in these gass 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 .In Tm 3+ \|Yb 3+ co\|doped AlF\-3\|based flouride glass,the concentration quenching of Tm 3+ in blue at 476?nm is stronger than that in infrared light at 793?nm,and the optimum content of Tm 3+ for 476?nm emission is about 0 1?mol%,while it is (0 3—5)mol% for 793?nm emission.The concentration quenching of Yb 3+ to upconvertion fluorescence is also observed.It may be due to the back\|energy transfer from the 3F 4 level of Tm 3+ to the 2F 5/2 level of Yb 3+ .