改进的反Stokes能量传递对ErP5O14非晶中荧光动力学研究的影响  

Influence of improved anti-Stokes energy transfer between rare earth ions in ErP_5O_(14) noncrystal on dynamic study

作　　者：陈英[1] 陈晓波[1] 张会敏[1] 徐晓灵 王策[1] 

机构地区：[1]北京师范大学应用光学北京市重点实验室,分析测试中心,北京100875

出　　处：《物理学报》2011年第7期743-748,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10674019)资助的课题~~

摘　　要：本文通过建立不同浓度五磷酸盐非晶材料(ErxLa1-xP5O14)动力学过程的速率方程,特别是引入了改进系数exp{hcv珋k/kT}以区别能量传递Stokes过程和反Stokes过程,分别对Er0.01La0.99P5O14,Er0.1La0.9P5O14,和ErP5O14非晶材料中979.3nm,803.8nm和521.8nm光激发下所有能级的动力学过程在改进能量传递理论前后进行了比较,结果发现,当稀土离子间距较小时(如在ErP5O14非晶中),考虑能量传递Stokes和反Stokes过程差别对计算模拟非常重要,说明此时能量传递起到了关键性作用.而离子间距较大时,则几乎无影响.并且发现全浓度ErP5O14非晶材料在可见光激发下存在红外量子剪裁现象.且详细计算了有关的无辐射弛豫速率、自发辐射速率和能量传递速率,分析了有关的能量传递动力学过程,发现速率为239500s-1的{2H11/2→4I9/2,4I15/2→4I13/2}交叉能量传递是导致光激发2H11/2能级的红外量子剪裁现象的主要原因,该研究对于寻找高效率的太阳能电池材料很有意义.Since the visible quantum cutting in Eu3＋ - Gd3＋ material was reported, the importance, the application, and the significance of the quantum cutting phenomenon have been widely recognized. The rate equations which describe the luminescence dynamic processes for different concentrations of （ErxLa1-sP5O14） noncrystal are established in this paper. The coefficients exp{ hcvk/kT} is introduced in to the calculation of anti-Stokes energy transfer rate to distinguish Stokes energy transfer. All dynamic processes have been simulated separately with and without considering this coefficient for the energy transfer rate of Er0.01 La0.99 P5O14 ,Er0.1 La0.9 P5O14 and ErP5O14 noncrystals when their ^2H11/ 2,^4I9/2 and ^4I11/2 levels are excited. The results show that it is essential to take the coefficient into calculation particularly for ErP5O14 noncrystal where energy transfer plays a key role. There is no influence though the distance between rare earth ions is larger. And it is found that infrared quantum cutting exsists in ErP5O14 nonerystal excited by visible light. The relative nonradiative relaxation rate, the spontaneous emission rate and the energy transfer rate are calculated particularly , The relative energy transfer dynamics is analyzed. It is found that the {4H11/2→^4I9/2,^4I15/2→^4I13/2 } energy transfer with a rate of 239500s^-1, is the main reason for ^2H11/2 energy level to have the infrared quantum cutting, Which is meaningful for finding high-efficiency solar cell materials.

关 键 词：反Stokes能量传递改进系数 动力学过程 五磷酸盐非晶 红外量子剪裁 

分 类 号：O482.31[理学—固体物理]