Yb^(3+)对Tm^(3+)间接敏化与基质晶格关系  

Indirect Sensitization Luminescence of Tm^(3+) by Yb^(3+) and Relation to Host Lattice

作　　者：臧竞存[1] 徐东勇[1] 邹玉林[1] 

机构地区：[1]北京工业大学材料科学与工程学院,北京100022

出　　处：《中国稀土学报》2001年第6期611-613,共3页Journal of the Chinese Society of Rare Earths

基　　金：北京市教委资助项目 ;中科院光物理开放实验室资助项目

摘　　要：Yb3+ 敏化Tm3+ 有两种方式 ,一种是直接敏化上转换 ,另一种是间接敏化上转换。前种直接采用 980nm激光激发 ,而后者可用 80 7nm激光激发 ,无疑后者有利于提高上转换发光的量子效率。由于基质晶格的晶体场强度不同 ,对称性有高有低 ,造成的稀土离子的能级分裂不同 ,通过分析双掺BaY2 F8,Cs3Yb2 Cl9等材料的光谱资料并结合生长的双掺Yb3+ ,Tm3+ ∶ZnWO4 单晶光谱的实际测试与分析 ,提出了Yb3+ 和Tm3+ 间的间接敏化共振能量传输的新观点 ,并具体分析了能形成这一上转换机制的条件。与间接敏化非共振能量传输不同 ,一是Yb3+ 的2 F5/2 →2 F7/2 的跃迁应与Tm3+ 3H4 →1 G4 能级间隔尽可能接近 ;二是Yb3+ 激发态能级2 F5/2 与Tm3+ 的3H4 能级尽可能接近。这要求基质材料的晶体场场强要弱 ,对称性要低。间接敏化共振能量传输极有可能引起光子雪崩上转换 ,这将为探索实用上转换激光晶体提供有益经验。There are two types of sensitization of Tm 3+ by Yb 3+ . One is a direct sensitization upconversion, and another is an indirect sensitization upconversion. In the former the Tm 3+ is excited by 980 nm laser, in the latter it is excited by 808 nm laser, consequently it has high quantum efficiency. On the basis of analyzing spectrum data of Yb 3+ , Tm 3+ codoped BaY 2F 8, CsYb 2Cl 9 and ZnWO 4 single crystals, we supposed that indirect sensitization luminescence and resonant energy transfer in Yb 3+ Tm 3+ . The condition of the upconversion is that the energy levels of the transition of 2F 5/2 - 2F 7/2 of Yb 3+ are approximate to 3H 4- 1G 4 of Tm 3+ and the energy levels 2F 5/2 excited state of Yb 3+ are approximate to 3H 4 of the Tm 3+ . The host materials have weak crystal field strength and low symmetry for photon avalanche.

关 键 词：稀土 间接敏化 共振传输 激光晶体 上转换发光材料 钨酸锌 铥 镱 上转换发光 基质 晶格 YB^3+ TM^3+ 

分 类 号：TN244[电子电信—物理电子学] O482.31[理学—固体物理]