Résumé:

We perform a careful study of the combined influence of the quantum well width and light polarization on the optical properties of strained GaN-AlGaN quantum wells oriented along the [0 0 0 1] direction. This is made in the context of a six-band envelope function approach together with utilization of the most recent experimental values of crystal field splitting, spin-orbit interaction and deformation potentials. We calculate the holes confinement, exciton binding energies and absorption spectra. We show that under sigma polarization conditions for chosen quantum wells, the only noticeable features can be attributed to enhanced A and B excitons; the C exciton process cannot be stimulated due to inter-valence band mixings. (C) 1998 Elsevier Science B.V. All rights reserved.