A comparative analysis of infra-red luminescence spectra of ZnSe crystals doped with Yb, Gd or Cr impurities

•IR luminescence spectra of ZnSe doped with Yb, Gd, or Cr have good coincidence.•The good correlation between the component parts of the bands at 1 and 2μm takes place.•Control of the composition of IR luminescence spectra by changing stoichiometric deviation is possible. Infra-red (IR) photoluminescence (PL) spectra of ZnSe crystals doped with Yb, Gd rare-earth impurities and Cr impurity are investigated. The influence of stoichiometric deviation on the spectra is studied and the structure of complex IR PL bands is analysed. The good coincidence between the structures of IR PL spectra of the samples doped with Yb, Gd, and Cr is shown. Correlation between the component parts of the bands at 1 and 2μm is found and possibility to control the composition of IR PL spectra by enrichment of the samples with Zn or Se is discussed. The models that explain the formation of complexes based on rare-earth and background Cr and Cu impurities, responsible for IR PL bands, are proposed. Keywords: IR luminescence, ZnSe, Rare-earth impurities, Cr impurity.