Optical spectroscopy of Sm3+ doped Na2O-ZnO-La2O3-TeO2 glasses

Telluride glasses with the composition xSm(2)O(3)-(7-x)La2O3-3Na(2)O-25ZnO-65TeO(2) (where x = 0.1, 1, 2, 5 and 7 mol%) were obtained by the melt quenching technique. Electronic absorption and fluorescence spectra as well as fluorescence dynamics of the Sm3+-doped title glasses are presented and analysed in detail. A Judd-Ofelt intensity analysis of the absorption spectrum at 300 K has been applied for determination of Omega(lambda) parameters (Omega(2) = 3.10, Omega(4) = 3.80, Omega(6) = 1.61 x 10(-20) cm(2)) which in turn have been used for calculations of the radiative transition probabilities (A(T)), the natural (radiative) lifetimes (tau(R)) of the (4)G(5/2) level of Sm3+, the fluorescence branching ratios (beta) and the emission cross-sections (sigma(em)). The tau(R) value of the (4)G(5/2) level amount to 1546 mu s and is slightly higher than the measured decay time of 1306 mu s. With the increasing of Sm2O3 concentration from 0.1 to 7.0 mol% the experimental lifetime of the fluorescent level decreases from 1306 to 41 mu s. An analysis of the non-radiative decay was based on the cross-relaxation mechanisms. The optical achieved results indicate that the investigated glasses are potentially applicable as an orange and/or red laser host. (C) 2015 Elsevier B.V. All rights reserved.