Rinker, M.M.RinkerKalt, H.H.KaltLu, Y.-C.Y.-C.LuGanser, P.P.GanserKöhler, KlausKlausKöhler2022-03-032022-03-031991https://publica.fraunhofer.de/handle/publica/180073The dependence of the bandstructure and the resulting dependences of the intensity and the wavelength of stimulated emission on the carrier density are demonstrated in optically excited AlxGa1-xAs near the crossover composition xc at room temperature. Density induced Gamma to L and Gamma to X crossings, based on the large band-gap renormalization near the crossover composition, are observed in samples with an AlAs mole fraction x equal 0.43 and x equal 0.46. The band crossings are indicated by strong fluctuations of the intensity and the wavelength of stimulated emission. This behavior is quantitatively well explained by using a multi-valley model for the description of the band-gap renormalization. The multi-valley model leads to an exact density-dependent prediction of the wavelength and to an estimation of the intensity of stimulated emission in indirect band-gap AlxGa1-xAs and shows the optimum AlAs mole fraction for semiconductor laser application.enIII-V HalbleiterIII-V semiconductorsphotoluminescencePhotolumineszenzstimulated emissionstimulierte Emission621667journal article