Optical and luminescent properties of Sm3+ doped tellurite glasses

Glasses with chemical composition of (62−x) TeO2 + 25 ZnO + 8 K2O + 5 CaO + x Sm2O3 (TZKCSmx; x = 0.1, 0.5, 1.0, 1.5 mol%) were prepared by melt quenching technique. The absorption spectrum was recorded in the UV–visible and NIR regions. The oscillator strengths of absorption bands were obtained by measuring the area under the bands. Judd–Ofelt analysis has been carried out to estimate the host dependent J–O intensity Ωλ (λ = 2, 4, 6) parameters by least squares fitting approach. Photoluminescence spectra recorded in the visible region revealed intense green, orange and red emission bands in all the glasses, corresponding to the 4G5/2→6H5/24G5/2→6H5/2, 4G5/2→6H7/24G5/2→6H7/2 and 4G5/2→6H9/24G5/2→6H9/2 transitions respectively. From the emission spectra and J–O intensity parameters, various radiative parameters were calculated from the excited 4G5/24G5/2 to the lower lying 6HJ6HJ (J = 5/2, 7/2, 9/2, 11/2) multiplet. Quenching of luminescence with the increase of Sm3+ ions concentration has been observed. Decay times of excited 4G5/24G5/2 state decrease with the increase of the Sm3+ ions concentration. The energy transfer mechanism that leads to the quenching of 4G5/24G5/2 state lifetime has been discussed. Inokuti–Hirayama (I–H) model was used to evaluate various energy transfer parameters, which are the qualitative indicators for the interaction among Sm3+ ions.

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► Glasses doped with various Sm2O3 concentrations were prepared by melt quenching.
► Optical absorption and photoluminescence spectra, decay profiles were recorded.
► Judd–Ofelt analysis has been carried.
► The effect of the concentration on the luminescence of Sm3+ ions has been discussed.
► The decay curves are analyzed with I–H model to elucidate type of interaction.