Thermally Activated Carrier Dynamics and Photoluminescence in Self-assembled InAs Quantum Dots

Two InAs/GaAs quantum dot (QD) heterostructures with different InAs active layer thickness were carried out. It is found that thickening the InAs active layer will enhance the dot density. By analyzing the temperature dependence of the photoluminescence (PL) spectra of the samples, the carrier thermal emission and recapture among dots affect the PL spectra of high density QDs evidently. Besides, the transferring rate of carriers from wetting layer into QDs plays an influential role in the dependence of the PL spectra on temperature for the low density QDs sample