Tight-binding model for the electronic and optical properties of nitride-based quantum dots

Two slightly different, efficient tight-binding (TB) models for the description of the electronic properties of nitride-based semiconductor quantum dots (QDs) have been developed and applied to the calculation of the electronic one-particle spectrum of these structures. Using these one-particle QD-states, dipole and Coulomb matrix elements can be calculated, from which the optical properties of these systems can be obtained. These TB calculations have been performed for nitride-based QDs with a cubic zincblende structure and those with a wurtzite crystal structure. In this paper, we discuss the general methodology used and the results obtained for the electronic one-particle states and energies, for the dipole and Coulomb matrix elements, and for the excitonic optical emission and absorption spectra.