1.3 μm emission from InAs/GaAs quantum dots

We report here the results of our photoluminescence study of a series of single quantum dot layer structures containing In,Gal,As strain reducing layers with different In concentration (from 0 % to 29 %), prepared by low pressure metal organic vapour phase epitaxy. These structures display a strong red shift of photoluminescence maxima from 1.25 mu m to 1.45 mu m at 300 K with increased In content in the ternary layer. The origin of the observed transitions has been explained using magnetophotoluminescence measurements and photoluminescence measurements for different pumping intensities at low temperature. Optical transition energies were calculated using a simple single-band effective mass model with energy-dependent effective mass. Comparing the calculated and measured energies, we can determine the thickness of the wetting layer and the sizes of the dots. (c) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.