Investigations of optical and luminescence features of Sm3+ doped Li2O-MO-B2O3 (M =Mg/Ca/Sr/Ba) glasses mixed with different modifier oxides as an orange light emitting phosphor for WLED's

Abstract

The glass composition of 50Li2O-20MO-29.7B2O3-0.3Sm2O3 (M = Mg/Ca/Sr/Ba), has been synthesized by the conventional melt quench technique. Density measurements were studied and shows large for LBaBSm glass sample (2.9049 g/cm3) than any other alkali species (Mg/Ca/Sr). Variation in density is due to the ionic radii of the alkali ion species (M = Mg/Ca/Sr/Ba). Optical absorption spectra of Sm3+ doped LMgB, LCaB, LSrB and LBaB glass systems were studied and shows very intense peaks at NIR region. The emission and excitation spectra of these glasses were studied and emission spectra shows green, yellow and reddish - orange emission bands at 563, 600, 646 and 706 nm. Judd–Ofelt (JO) intensity analysis had been performed and JO parameters were estimated for 0.3 mol.% Sm2O3 doped 50Li2O-20MO-29.7B2O3 (M = Mg/Ca/Sr/Ba) glasses. Radiative properties such as transition probabilities, stimulated emission cross-sections and branching ratios were estimated by using JO parameters and luminescence spectra. The decay curves of these glasses exhibit single exponential nature. The CCT values obtained from CIE for these glass samples shows 1663 K for indicating orange emission under 403 nm excitation wavelength.