Investigation on luminescence properties of Nd3+ ions in alkaline-earth titanium phosphate glasses

Nd3+ ions doped alkaline-earth titanium phosphate glasses were prepared by using the conventional melt quenching method. Absorption spectra were recorded and oscillator strengths of the transitions were calculated using area under the absorption bands. The energy level analysis was carried out by using free-ion Hamiltonian model. The three host dependent Judd–Ofelt intensity parameters, Ωλ (λ = 2, 4, and 6) were used to elucidate the structure of glassy matrix around Nd3+ ion as well as to determine the 4F3/2 metastable state radiative properties such as radiative transition probabilities, branching ratios and radiative lifetimes. The decay curves of all the three glasses show single exponential behavior. The discrepancy between the experimental and calculated lifetimes of emitting level was attributed to multiphonon relaxation. The achieved high quantum efficiencies for the 4F3/2 level indicate efficient laser emission at 1.06 μm in these glass systems.