双模自组织量子点光致发光的温度依赖性  

Temperature Dependence of Photoluminescence in Self-assembled Bimodal Quantum Dots

作　　者：邓浩亮[1] 姚江宏[2] 

机构地区：[1]天津工程师范学院数理系,天津300222 [2]南开大学弱光非线性光子学教育部重点实验室,天津300457

出　　处：《发光学报》2008年第6期1023-1026,共4页Chinese Journal of Luminescence

基　　金：天津工程师范学院科研基金(KJ2006-028);天津应用基础研究计划(08JCYBJC14800;06YFJZJC01100);国家自然科学基金(60476042);"863"计划(2006AA03Z413);"973"计划(2006CB921703)资助项目

摘　　要：采用稳态速率方程模型,对双模自组织量子点光致发光的温度依赖性进行了研究,模拟获得了不同温度下双模自组织量子点的光致发光光谱,并进一步研究了两组量子点分布的光致发光强度比的温度依赖性。研究表明:在低温下(<75K),两组量子点分布的发光强度比基本保持不变;随着温度的升高(75K<T<150K),两组量子点分布的发光强度比将持续增大,且当温度为150K时达到峰值;当温度高于转折温度(150K)后,两组量子点分布的发光强度比显著减小。The study on the temperature dependence of photoluminescence （PL） is essentially important for clarifying the processes of energy relaxation and energy transfer in the self-assembled quantum dots （QDs）.The unusual dependence on temperature of both the peak energy position and the width of the PL hands has been reported, The tast redshift of PL energy and the anomalous decrease of line-width with increasing temperature have been attributed to thermally enhanced carrier relaxation between quantum dots due to cartier therreal emission and carrier transport through the wetting laver. The PL intensity quenches with temperature due to carrier thermal escape from the dot ground states to the states of the matrix material and/or nonradiative recombination centers. In this paper, the temperature dependenc, e of the PL of self-assembled bimodal QDs was simulated by using a steady-state rate equation model. The temperature dependence of PL intensity ratio of two QDs populations was emphatically investigated. The results showed that, the intensity ratio remains constant at low temperature （ 〈75 K） and increases continuously at intermediate temperature（75 K 〈 T〈 150 K） ; when the temperature is raised above 150 K, the intensity ratio has an abnormal decrease.

关 键 词：双模自组织量子点 光致发光 热激发 

分 类 号：O472.3[理学—半导体物理] O482.31[理学—物理]