Optical properties of GaN/${\mathrm{Al}}_x{\mathrm{Ga}}_{1-x}$N quantum wells

The optical properties of GaN/${\mathrm{Al}}_x{\mathrm{Ga}}_{1-x}$N quantum wells have been investigated by means of various spectroscopic techniques. A detailed assessment of the electronic and excitonic states has been obtained by comparing the temperature and intensity dependent luminescence and luminescence excitation spectra to the calculated band alignment and confinement energies of the quantum well. Room temperature stimulated emission due to localized exciton states is demonstrated by magnetoluminescence experiments under a strong injection rate.