Tailored spectroscopic characteristics of Sm3+-imbued zinc-sodium tellurite glasses: influence of Dy3+co-doping

Abstract

The effects of Dy3+ co-doping on the spectroscopic properties of Sm3+-imbued zinc-sodium tellurite glasses were examined. These glasses of the form (59.2 – z) TeO2 – 25ZnO – 15Na2O – 0.8Sm2O3 – zDy2O3; where z = 0.0, 0.4, 0.8, 1.2, 1.6, and 2.0 mol% were prepared using melt-quenching approach and characterized. XRD and EDX analyses of the samples confirmed their amorphous nature and stoichiometric elemental compositions, respectively. FTIR analyses of the samples revealed the conversion of TeO4 to TeO3 structural units. The glass density was increased with the increase of Dy3+ contents. The absorption spectra of glasses displayed eighteen characteristic peaks in the range of 300–1800 cm−1 due to various electronic transitions in Sm3+ and Dy3+. The Urbach energy (0.155–0.251 eV), refractive index (2.249–2.283 eV), both direct (3.585–3.704 eV) and indirect (3.455–3.609 eV) optical band gap energy of the glasses were significantly affected due to co-doping. The luminescence spectra of the glasses exhibited six significant peaks in the wavelength range of 400–750 nm under different excitations. The chromaticity coordinates of the glasses were determined by the CIE 1931 diagram. The recorded luminescence lifetime decay analyses of the glasses showed a maximum energy transfer efficiency of 72% for TZNSD0.4 glass. It was demonstrated that the spectroscopic attributes of the proposed glasses can be customized via Dy3+ co-doping. These glasses may be useful for the solid-state lasers and displays.