Thermal annealing effect on the intersublevel transitions in InAs quantum dots

Isochronal thermal annealing effect on the photoluminescence (PL) spectra o f intersublevel transitions in InAs self-assembled quantum dots was investi gated. Several peaks due to intersublevel transitions in the quantum dots w ere observed in the PL spectra of two samples consisting of 10 stacks of In As quantum dots and InP barriers. Isochronal furnace annealing in the tempe rature range of 500-800 degreesC was conducted on the two samples. The resu lts show that the intensity of the PL peaks was dramatically reduced, and a new peak attributed to the wetting layer was observed after the samples we re thermally annealed above 550 degreesC. A small blue shift of the PL peak s due to intermixing was observed. (C) 2001 American Institute of Physics.