Spectroscopic investigations on multi-channel visible and NIR emission of Sm~(3+)-doped alkali-alkaline earth fluoro phosphate glasses

摘要

The optical spectroscopy of multichannel visible and NIR emission characteristics of Sm3+-doped alkali-alkalinefluoro phosphate glasses with molar composition of PKAXfNfSm1.0:45P(2)O(5) + 15K(2)O + 10Al(2)O(3) + 19XF(2) + 10NaF(2) + 1Sm(2)O(3), (where X = Mg, Ca, Sr and Ba) were studied through absorption, emission and luminescence decay curves. Based on the absorption spectra and Judd-Ofelt (JO) theory, the JO intensity parameters (Omega(lambda), lambda = 2, 4 and 6) were determined and then used to predict the radiative properties for various excited levels of Sm3+ ion. Stimulated emission cross-sections (sigma(lambda(p))) were evaluated for (4)G(5/2) - H-6(5/2.7/2. 9/2.11/2) and (4)G(5/2) - F-6(3/2.5/2.7/2.9/2) transitions. The radiative lifetimes (tau(R)) calculated from JO theory and the measured lifetimes (tau(exp)) determined from experimental decay curves for (4)G(5/2) level were employed to estimate the quantum efficiency for (4)G(5/2) level of Sm3+ ions in PKAMfNfSm1.0, PKACfNfSm1.0, PKASfNfSm1.0 and PKABfNfSm1.0 glasses and are found to be 73, 74, 72 and 78%, respectively. Among all these PKAXfNfSm1.0 glasses, the PKABfNfSm1.0 glass exhibits higher quantum efficiency. The chromaticity coordinates determined from the emission spectra were lying in the orange-reddish region for PKAXfNfSm1.0 glass systems. All the results indicate that the studied glasses could be potential candidates for applications in widely used compact light sources, optical and infrared optoelectronic devices.