Hybridized quantum dot-wetting layer states in photoluminescence of In(Ga)As/GaAs dot chain samples

The effects of electronic wave function hybridization are studied in In (Ga)As/GaAs dot chain samples by means of continuous wave and time resolved photoluminescence (PL). A set of wetting layer (WL) states strongly coupled with the quantum dot (QD) heavy hole states is revealed in the PL. The hybridization of states is favored by the presence of a specific one-dimensional postwetting layer that strings together the QDs in each chain. It is demonstrated that the strength of hybridization is significantly weakened for states deep in the WL gap. The hybridization of the WL states and the QD hole states substantially affects the rates of carrier trapping by the QDs and the carrier distribution. Specific convex shape of the PL transients is related to the presence of long living localized states in the WL energy gap. (c) 2009 American Institute of Physics. [DOI: 10.1063/1.3151707]