Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1545287 | Physica E: Low-dimensional Systems and Nanostructures | 2009 | 6 Pages |
Abstract
An effective approach for describing the electronic structure of InGaAs/GaAs quantum dots (QDs) is presented. We model QDs based on a single sub-band approach with an energy-dependent electron effective mass. The model assumes that the total effect of inter-band interactions, strain and piezoelectricity can be taken into account by an effective potential. Using this approximation, we define a strength parameter of the effective potential to reproduce capacitance-gate-voltage (CV) experimental data for InAs/GaAs QDs. In the present work, we expand the model to describe InxGa1âxAs QDs with significant Ga fractions. We find that our model accurately describes CV and photoluminescence (PL) data for QDs, assuming 22% Ga fractions, and also reproduces the experimental data for Coulomb shifts of exciton complexes (Xâ, X+, XX). We compared our results with those from atomistic pseudopotential and eight-band kp-Hamiltonian approaches. The strength of the electron and heavy hole confinements is found to be weaker in the kp-model than in the atomistic pseudopotential approach.
Related Topics
Physical Sciences and Engineering
Materials Science
Electronic, Optical and Magnetic Materials
Authors
I. Filikhin, V.M. Suslov, M. Wu, B. Vlahovic,