Perturbative effects on the optical extinction of GaN/AlN spherical QD in 0–0.5 eV range

The optoelectronic properties of quantum nanostructures are determined by their sizes and energy states affected by external electric field. The IR subband optical absorption of zinc-blende GaN/AlN spherical quantum dots (QDs) is obtained from perturbed energy states. The static dielectric constant and associated functions for broadened general absorption in the strong absorptive region are obtained from an improved iterative density matrix. These functions are also verified via Kramers–Kronig relations for a 4 nm zinc-blende GaN/AlN heterocrystal QD. The dielectric constants obtained for QDs in this study are well-matched with the bulk dielectric constant of GaN. Additionally, it is observed that the electric field effect dominates at the above of excitonic radius, while size effects significantly alter subband energies for smaller QD radius. As a perturbative result, forbidden transition-peaks in the presence of the electric field are also obtained at sizes of QD radii 5 nm and 6 nm.