Growth optimization of self-organized InSb/InAs quantum dots

The authors report the growth optimization of InSb/InAs quantum dots (QDs) by molecular beam epitaxy (MBE). QDs morphology and optical properties were investigated by atomic force microscope and photoluminescence (PL). We observed that the migration enhanced epitaxy technique without the annealing stage is a superior method for producing high quality coherent QDs with a high density of similar to 1.2 x 10(10) dots cm(-2). PL emission from buried InSb/InAs QDs was observed at low temperatures at a wavelength near 3.3 mu m. In addition, the emission efficiency was dramatically improved for the samples where the InAs cap layer was grown at a lower temperature, indicating that low growth temperatures are required to maintain good properties of QDs which is due to reduced As/Sb exchange.