A series of Sm3+-doped sodium tellurite glasses co-doped with Yb3+were synthesized by melt quenching technique. The amorphous nature of the glasses was confirmed by X-Rays diffraction technique. From UV-Vis-NIR spectroscopy, eight absorption peaks of Sm3+ions are observed. The broad absorption band in the range of ~870-1100 nm corresponds to the superposition of Sm3+:6H5/26F11/2and Yb3+:2F7/22F5/2transitions. The experimental and theoretical oscillator strengths of these bands were calculated by Judd-Ofelt theory. The optical band gap energy (Eopt) values for direct allowed transition and Urbach energy were found to be in the range of 2.73-2.91 eV and 0.21-0.27 eV respectively. Four luminescence emission bands4G5/26H5/2,6H7/2,6H9/2and6H11/2were revealed under 406 nm excitation and intensity of all bands is found to be quenched with addition of Yb3+ions. The role of Yb3+co-doping in the optical properties is compared and understood.
UV–Vis-NIR spectroscopy, structural and thermal properties of novel oxyhalide tellurite glasses with composition TeO2-B2O3-SrCl2-LiF-Bi2O3 for optical application
