The optical properties of GaN/AlxGa1-xN quantum wells have been invest
igated by means of various spectroscopic techniques. A detailed assess
ment of the electronic and excitonic states has been obtained by compa
ring the temperature and intensity dependent luminescence and luminesc
ence excitation spectra to the calculated band alignment and confineme
nt energies of the quantum well. Room temperature stimulated emission
due to localized exciton states is demonstrated by magnetoluminescence
experiments under a strong injection rate.