Temperature dependence of band gap energies of GaAsN alloys

The temperature dependence of band gap energies of GaAsN alloys was studied with absorption measurements. As the N concentration in GaAsN increased, t he temperature dependence of the band gap energy was clearly reduced in com parison with that of GaAs. The redshift of the absorption edge in GaAsN for the temperature increase from 25 to 297 K was reduced to 60% of that of Ga As for the N concentration larger than similar to 1%. The differential temp erature coefficient of the energy gap at room temperature was also reduced to 70% of that of GaAs. The main factor for this reduced temperature depend ence in GaAsN was attributed to the transition from band-like states to nit rogen-related localized states with detailed studies of the temperature-ind uced shift of the absorption edge. (C) 2000 American Institute of Physics. [S0003-6951(00)04110-3].