[Photoluminescence investigation of InAs bimodal self-assembled quantum dots state filling].
Self-assembled InAs quantum dots were prepared on GaAs(100) substrate in a solid source molecular beam epitaxy system. The distribution and topographic images of uncapped dots were studied by atomic force microscope. The statistical result shows that the quantum dots are bimodal distribution. The photoluminescence spectrum results shows that the intensity of small size quantum dots dominated, which may be due to: (1) the state density of large quantum dots lower than that of small quantum dots; (2) the carriers capture rate of large size quantum dots is small relative to that of small ones; (3) there is a large strain barrier between large quantum dots and capping layer, and the large strain is likely to produce the defect and dislocation, resulting in a probability of carriers transferring from large quantum dots to small dots that is very small with temperature increasing.
Jia
Guo-Zhi
GZ
The Key Lab of Advanced Technique and Fabrication for Weak-Light Nonlinear Photonics Materials, Ministry of Education, TEDA Applied Physics School, Nankai University, Tianjin 300475, China.
Yao
Jiang-Hong
JH
Zhang
Chun-Ling
CL
Shu
Qiang
Q
Liu
Ru-Bin
RB
Ye
Xiao-Ling
XL
Wang
Zhan-Guo
ZG