红外与毫米波学报, 2005, 24 (3): 207, 网络出版: 2006-05-10
大尺寸InAs/GaAs量子点的静压光谱
PHOTOLUMINESCENCE OF LARGE- SIZED INAS/GAAS QUANTUM DOTS UNDER HYDROSTATIC PRESSURE
摘要
在低温15K和0~9GPa范围内对厚度为7.3nm、横向尺寸为78nm的自组织InAs/GaAs量子点进行了压力光谱研究.观测到大量子点的基态与第一激发态发光峰,其压力系数只有69和72meV/GPa,比小量子点的压力系数更小.基于非线性弹性理论的分析表明失配应变与弹性系数随压力的变化是大量子点压力系数小的主要原因之一.压力实验结果还表明大量子点的第一激发态发光峰来源于电子的第一激发态到空穴的第一激发态的跃迁.
Abstract
The photoluminescence of self-assembled InAs/GaAs quantum dots, which are 7.3nm in height and 78nm in base size, was investigated at 15K under hydrostatic pressures up to 9GPa. The emissions from both the ground and the first excited states in large InAs dots were observed. The pressure coefficients of the two emissions are 69 and 72 meV/GPa respectively, which are lower than those of small InAs/GaAs dots. The analysis based on a nonlinear elasticity theory reveals that the small pressure coefficients mainly result from the changes of the misfit strain and the elastic constants with pressure. The pressure experiments suggest that the excited state emissions originate from the optical transitions between the first excited electron states and the first excited hole states.
马宝珊, 王晓东, 骆军委, 苏付海, 方再利, 丁琨, 牛智川, 李国华. 大尺寸InAs/GaAs量子点的静压光谱[J]. 红外与毫米波学报, 2005, 24(3): 207. 马宝珊, 王晓东, 骆军委, 苏付海, 方再利, 丁琨, 牛智川, 李国华. PHOTOLUMINESCENCE OF LARGE- SIZED INAS/GAAS QUANTUM DOTS UNDER HYDROSTATIC PRESSURE[J]. Journal of Infrared and Millimeter Waves, 2005, 24(3): 207.