Fluorescence line narrowing spectral studies of Eu3+-doped lead borate glass

A lead borate glass of molar composition 49.5H3BO3-49.5PbO-1.0Eu2O3 was prepared and studied by broadband and fluorescence line narrowing spectral techniques. Site-selective 5D0 → 7F0,1 emission spectra were obtained under resonant excitation at different wavelengths along the 7F0 → 5D0 transition. These studies have been used to investigate the site-to-site variations in the spectroscopic properties of Eu3+ ions in the lead borate glass at 13 K. The energies of the Stark levels of the 7F1 multiplets are obtained from the experimental fluorescence line narrowing spectra and crystal-field analysis has been carried out, assuming C2v orthorhombic symmetry, for each of the excitation energies. The distribution environments and the local structures of Eu3+ ions in lead borate glass are found to be almost similar to calcium diborate glass and lies intermediate between Eu3+-doped sodium borosilicate and lithium fluoroborate glasses.