Band Gap Engineering of host GaAs through deposited PbS quantum dots

The hetero-pairing of colloidal quantum dots (QDs) with semiconducting hosts considerably enlarges the technological application bandwidth of this material platform, which suits mass-market production. In this talk, we report photoluminescence studies in solvent deposited PbS quantum dots on undoped GaAs substrates. The QD thin films were characterized by transmission (TR), reflection (RE) and photoluminescence (PL) measurements as well as transmission electron microscopy (TEM). In the PL measurements, we see alteration of the optical emission by the electronic influence of the deposited QDs. Our previous work has demonstrated an enhancement of GaAs PL in presence of PbS QD, and a follow up is needed to fully understand the potential of the process. Through this work, we attempt to reconcile the observations from PbS QD experiments with the already reported classical models in semiconductor heterostructures. The findings give new insights in optical device engineering using charge transfer between bulk and quantized matter.