Visible and NIR spectral analysis of Er³⁺ doped LiBiAlBSi glasses for laser applications

The lithium bismuth alumino borosilicate (LiBiAlBSi) glasses incorporated with different concentrations (0.1 to 2 mol%) of Er³⁺ ions were formed through the melt quench technique. Studies on optical absorption, photoluminescence, and decay profiles were performed. Detailed analysis of absorption and emission spectra was done by applying Judd- Ofelt (JO) theory. Under an excitation wavelength of 378 nm, the samples show intense green and NIR emission corresponding to transitions ⁴S_3/2 → ⁴I_15/2 (547 nm) and ⁴I_13/2 → ⁴I_15/2 (1538 nm), respectively. Dexter theory was applied to the NIR emission spectra to confirm the dipole–dipole nature of interaction among the Er³⁺ ions. CIE coordinates for the visible spectra lie in the green region. Various parameters such as stimulated emission cross-section, optical gain, and gain bandwidth for the as-prepared glasses show that these glasses exhibit good luminescence behavior and that the optimized LiBiAlBSiEr10 glass is ideal for laser applications in visible and NIR regions.