Interband emission and normal-incidence intraband absorption in (In,Ga)As quantum-dot nanostructures

This paper reports on interband emission and intraband absorption processes in doped InGaAs/GaAs quantum-dot nanostructures as the measurement temperature is varied. An analysis of the data yields useful insight into the carrier redistribution mechanisms that occur as a result of dot-size variation. For the samples studied, the size distribution is bimodal; this is reflected in the results obtained from the interband emission, as well as in the intraband absorption data. The understanding gained from studies such as these is important in the design of quantum-dot optoelectronic devices intended for room-temperature operation.