Transition metal (Cr 3+) and rare earth (Eu 3+, Dy 3+) ions used as a spectroscopic probe in compositional-dependent lead borate glasses

Abstract

Compositional-dependent lead borate glasses doped with transition metal and rare earth ions were studied using absorption and luminescence spectroscopy. The trivalent Cr 3+, Eu 3+ and Dy 3+ ions were used as a spectroscopic probe in glass samples with various PbO/B 2O 3 ratios. Spectral analysis indicates that Cr 3+ ions occupy intermediate field sites; the both sites coexist and emit from the 4T 2 (low-field) and the 2E (high-field) states, respectively. The R and Y/ B values due to 5D 0– 7F 2/ 5D 0– 7F 1 and 4F 9/2– 6H 15/2/ 4F 9/2– 6H 13/2 luminescence intensity ratios of Eu 3+ and Dy 3+ ions, respectively, increase with increasing heavy metal (PbO) content, suggesting higher asymmetry and more covalent bonding character between rare earth and oxygen ions.