Penetration of electronic perturbations of dilute nitrogen impurities deep into the conduction band of GaP1-xNx -: art. no. 161304

The electronic structure consequences of the perturbations caused by dilute nitrogen impurities in GaP are studied by means of supercell calculations using a fully atomistic empirical pseudopotential method. We find that numerous localized states are introduced by a single N atom and N clusters, not only close to the band edge but also throughout the GaP conduction band, up to similar to1 eV above the conduction band edge. These localized states suggest an alternative interpretation for a previously puzzling observation of splitting of photoluminescence excitation intensity at the GaP Gamma(1c) energy into two features, one blueshifting and the other staying pinned in energy with increasing N concentration.