Physical and optical properties of Nd3+ co-doped Al in sol-gel silicate glasses

The optical properties of varying concentrations of Nd3 + ions co-doped with Al in the chemical compositions (80-x)SiO2 + 20Al(2)O(3) + xNdF(3) (SiAlNd), where x = 0.6, 1.2, 1.8, and 2.4 mol%, were investigated using the sol-gel method. Structural characterization was carried out using XRD and FTIR techniques. It was found that the polarizability of oxide ions increased with the concentration of rare earth ions, as evidenced by the observed values of density, refractive index, and Nd3+ ion concentration in the glasses. Even after heating to 800 degrees C, XRD results indicated that the prepared glass samples remained amorphous. FTIR was employed to identify the functional groups present in the synthesized sol-gel silica glass. The UV-Vis-NIR absorption spectra revealed seven peaks, corresponding to the excitation of electrons from the ground state I-4(9/2) to (4)G(9/2) (similar to 513 nm), (4)G(7/2) (similar to 528 nm), (4)G(5/2) + (2)G(7/2) (similar to 585 nm), H-2(11/2) (similar to 622 nm), F-4(9/2) (similar to 684 nm), F-4(7/2) + S-4(3/2) (similar to 747 nm), F-4(5/2) + H-2(9/2) (similar to 807 nm), and F-4(3/2) (similar to 878 nm). The Judd-Ofelt intensity parameters were derived from the absorption spectra of Nd3+-co-doped alumino-silicate glass. The fluorescence properties were also examined by assessing the radiative lifetime (tau(R)), luminescence branching ratio (beta(R)), and spontaneous transition probability (A(R)).