Five InAs/InxGa1-xAs quantum dots in a well (DWELL) with different indium concentration x are grown by solid source molecular beam epitaxy. The high quantum dot density is observed in the InAs/In0.3Ga0.7As DWELL. Th...Five InAs/InxGa1-xAs quantum dots in a well (DWELL) with different indium concentration x are grown by solid source molecular beam epitaxy. The high quantum dot density is observed in the InAs/In0.3Ga0.7As DWELL. The photoluminescence (PL) experiments indicate that the ground state peaks of InAs/In0.15 Ga0.85As and InAs/In0.22 Ga0.78As DWELLs shift to 1.31 and 1.33μm, respectively. The optical properties are investigated by using the PL and piezoreflectance spectroscope methods. An abnormal blue shift has been observed with the further increase of x from 0.22 to 0.30.展开更多
The photoluminescence spectrum (PL) of InAs quantum dots (QDs) at 80 K is studied by comparison between the theoretical calculation and experimental measurement. The Gaussian line shape is used to approximate the ...The photoluminescence spectrum (PL) of InAs quantum dots (QDs) at 80 K is studied by comparison between the theoretical calculation and experimental measurement. The Gaussian line shape is used to approximate the size distribution of QDs. Its mean volume and the standard full width at half maximum (FWHM) of the PL spectrum. size deviation are well correlated with the peak and The experimental PL spectrum is well reproduced by the theoretical model based on the effect mass approximation including the size distribution without any adjustable parameters. Compared with the standard size deviation value σ = 9 × 10^-2 determined by atomic force microscopic method a small value σ = 7 × 10^-2 is obtained by the best fitting process from the measured and calculated PL spectra.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 60567001, and the Cultivated Foundation for the 'Academic Cadreman of Yunnan University'
文摘Five InAs/InxGa1-xAs quantum dots in a well (DWELL) with different indium concentration x are grown by solid source molecular beam epitaxy. The high quantum dot density is observed in the InAs/In0.3Ga0.7As DWELL. The photoluminescence (PL) experiments indicate that the ground state peaks of InAs/In0.15 Ga0.85As and InAs/In0.22 Ga0.78As DWELLs shift to 1.31 and 1.33μm, respectively. The optical properties are investigated by using the PL and piezoreflectance spectroscope methods. An abnormal blue shift has been observed with the further increase of x from 0.22 to 0.30.
基金Supported by the National Natural Science Foundation of China under Grant No 10474020, the National Basic Research Programme of China under Grant No 2006CB13921507, and the Knowledge Innovation Project of Chinese Academy of Sciences.
文摘The photoluminescence spectrum (PL) of InAs quantum dots (QDs) at 80 K is studied by comparison between the theoretical calculation and experimental measurement. The Gaussian line shape is used to approximate the size distribution of QDs. Its mean volume and the standard full width at half maximum (FWHM) of the PL spectrum. size deviation are well correlated with the peak and The experimental PL spectrum is well reproduced by the theoretical model based on the effect mass approximation including the size distribution without any adjustable parameters. Compared with the standard size deviation value σ = 9 × 10^-2 determined by atomic force microscopic method a small value σ = 7 × 10^-2 is obtained by the best fitting process from the measured and calculated PL spectra.