非对称双量子阱中载流子耦合的温度依赖性  

Temperature Dependence of Carrier Coupling in an Asymmetric Double-Quantum-Well

作　　者：邓浩亮[1,2,3] 贾国治[1,2,3] 姚江宏 徐章程[1,2,3] 

机构地区：[1]南开大学弱光非线性光子学材料先进技术及制备教育部重点实验室 [2]信息光子材料与技术重点实验室 [3]泰达应用物理学院,天津300457

出　　处：《发光学报》2005年第6期753-756,共4页Chinese Journal of Luminescence

基　　金：国家自然科学基金(60476042;60444010);南开大学人事处科研启动经费资助项目

摘　　要：非对称双量子阱中载流子动力学过程的温度依赖性研究,对于实现室温下高效的量子阱光电器件有着非常重要的意义。随着温度的升高,量子阱中的载流子被热激发到势垒层中后,部分载流子会被量子阱再俘获,即在不同的量子阱之间发生了载流子的耦合。利用耦合多量子阱载流子动力学模型,模拟了非对称双量子阱中载流子耦合的温度依赖性。研究表明,在不同温度下,各量子阱的光致荧光强度比强烈地依赖于量子阱的激活能差。光致荧光强度比的最大值与激活能差成指数关系,而其所对应的温度与激活能差成线性关系。The understanding of the temperature dependence of carrier dynamics in an asymmetric doublequantum-well is essentially important for the realization of room temperature efficient photonic devices. As the temperature increases, the carriers will be thermally evaporated into the barrier layer from quantum wells and then some of them will be recaptured by the quantum wells, i.e. carrier coupling takes place between the different quantum wells when the temperature increases. The ratio of photoluminescence intensity of different quantum wells can reflect the distribution of carriers in each well. The temperature dependence of the ratio of photoluminescence intensity in an asymmetric doublequantum-well has not been reported until now. The temperature dependence of the carrier coupling in an asymmetric double-quantum-well was simulated by using the coupling multiple-quantum-well model of carrier dynamics. It is shown that the ratio of photoluminescence intensity of each well strongly depends on the difference of thermal activation energies. The maximum of the ratio of photoluminescence intensity depends exponentially on the difference of thermal activation energy, while the temperature corresponding to the maximum depends linearly on the difference of thermal activation energies. This simulation method can be used to study carrier thermal escape and re-trapping in quantum-dot-quantum-well heterostructures formed by sub-monolayer deposition, which will be published in the near future.

关 键 词：非对称双量子阱 光致荧光强度比 热逃逸 再俘获 

分 类 号：O472.3[理学—半导体物理] O482.31[理学—物理]