Self-consistent calculations of the optical properties of GaN quantum dots

We present calculations of the transition energies and radiative lifetimes in GaN quantum dots embedded in AlN. The effects of elastic strains, and piezoelectric and pyroelectric fields are included. The electronic structure is described using a tight-binding method which takes into account the screening of the internal electric field by excited carriers in a fully self-consistent procedure. We show that the presence of one electron-hole pair in a quantum dot increases the optical gap by a few tens of meV and decreases significantly the radiative lifetime, which could give rise to very interesting nonlinear optical effects.