Photoreflectance spectroscopy of InAs/GaAs quantum dots by using a bright configuration

The present study looks into the temperature-dependent optical properties of InAs/GaAs quantum dots (QDs) by using a bright configuration of photoreflectance spectroscopy (BPR). BPR has the great advantage of being able to remove the background noise effectively, and by using BPR, one can measure the photoreflectance (PR) and the photoluminescence (PL) signals simultaneously. The result shows that the intensity of the PL-related QD peak increases and the amplitude of the PR-related GaAs peak decreases as a result of a decrease in the modulation efficiency. The BPR intensity ratio of the PL-related QD peak to the PR-related GaAs peak linearly decreases as the temperature of the sample is increased. An increase in the radiative recombination causes a decrease in the modulation strength.