Optical investigation of GaAs_1−xN_x/GaAs heterostructure properties

Abstract

Abstract We have investigated, by photoluminescence (PL), the optical properties of GaAs 1− x N x /GaAs epilayers and GaAs 1− x N x /GaAs quantum well (QW) structures grown by metal organic vapor phase epitaxy (MOVPE) on (001)‐oriented GaAs substrates. Different behaviors have been observed for the bulk epilayer and for the QW structures, respectively: (i) a blue shift of the PL bands in both kinds of structures when increasing the excitation density, (ii) an S‐shaped PL peak energy versus temperature dependence has been observed for the GaAsN epilayer but a usual behavior is obtained for the QWs. Based in these experimental results, we have suggested that the carrier recombination mechanisms in the epilayer and in the quantum well structure are different. An enhanced exciton‐localization‐like mode for the epilayer is observed. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)