Optical properties of (001) GaN/AlN quantum wells

The absorption coefficient and the photoluminescence of (001) GaN/AlN quantum wells are calculated for several values of the well width, with and without the excitonic effect corrections, in the usual monoelectronic approach and as a many-body problem. The calculation was performed considering separate isolated bands for electrons, heavy and light holes. The monoelectronic approach to the optical properties was performed by assuming infinite well walls and finite well walls, respectively. The calculation including the excitonic effect as a many-body problem was performed within a recent approach designed for low-dimensional systems. The different wells studied here present many localized states and a complicated absorption spectrum. The monoelectronic approach in the infinite quantum well approximation reproduces quite well the spectrum of the wide wells due to the fact that the ground states of electrons and holes are well fixed by this model of quantum well.