作　　者： ; ; (等）;

机构地区： 中国科学技术大学化学与材料科学学院中国科学院结构分析重点实验室

出　　处： 《物理学报》 2001年第2期329-334,共6页

摘　　要： 基于以前综合V F模型 (考虑施主 受主 (D A)能量传递 )和B模型 (考虑施主 施主 (D D)能量迁移 )而提出的V F B综合模型 ,对La1-xErxF3 体系中Er3 +离子四种低掺杂浓度下 (x =0 0 0 1,0 0 0 3,0 0 1,0 0 2 ) 2 95K时4 S3/2 →4 I15/2 发光的时间演化曲线成功地重新进行了数值拟合 .结果表明该体系内D A间交叉弛豫能量传递是偶极 偶极作用 ,作用常数CDA为 4 75× 10 -4 1cm6/s,与Okamoto等人原用Y T扩散模型得到的结果一致 .而拟合得到的四个D D平均跳跃时间τ0 粗略地与xDα 次方 (xD 为D离子浓度 )成正比 (α≈ - 1 2 37) ,并不遵从τ0 很小时与xD 的- 2次方成正比的理论关系 .同时 ,通过把D D迁移和D A传递同时同样地纳入V F模型还粗略估计了D D平均跳跃时间τ0 ′的值 ,发现它与V F B给出的τ0 拟合值比较一致 ,说明V F B模型在一定近似程度上是内部自恰的、合理的 . By Application of the V\|F\|B model which is obtained by combining the Vasquez\|Flint (V\|F) model for donor\|acceptor energy transfer and the model of Burshtein for donor\|donor energy migration, the experimental luminescence decay curves of 4S 3/2 state of Er 3+ in LaF\-3 at 295K for four different concentrations are re\|simulated successfully.It is found that in this system the donor\|acceptor interaction is dipole\|dipole interaction,and that the donor\|acceptor interaction constant C DA is 4.75×10 -41 cm\+6/s. The results are all in agreement with the previous results of Okamoto. However, the hopping time τ \-0 obtained from the above simulation in proportional to x D -1.237 ( x D is the donor concentration), which is different from the theoretical dependence on the donor concentration (that is τ \-0 ∝ x D -2 ). In addition, by considering donor\|acceptor energy transfer and donor\|donor energy migration within the V\|F model at the same time, we obtain the estimated values of the hopping time τ\-0′ for four different concentrations, which are in reasonable agreement with the values of τ \-0 obtained from the above simulation.It seems that the V\|F\|B model is rather self\|consistent.

关 键 词： 能量传递 能量迁移 跳跃时间 交叉弛豫 稀土离子发光体系

领　　域： [理学] [理学]