Energy transfer process and radiative properties of 1.06 µm emission in Nd3+ doped TeO2-ZnO-Na2O glasses

In the present work, Nd3+ ions doped TeO2-ZnO-Na2O tellurite glasses were prepared using melt quenching method. Optical absorption, near-infrared emission, decay of Nd3+: 4F3/2 level were characterized. Judd-Ofelt intensity parameters (Ωλ, λ = 2, 4 and 6), radiative transition probabilities (Arad), radiative lifetimes (τrad) and branching ratios (β) for the Nd3+: 4F3/2 emitting level were estimated. The three emission bands, 4F3/2→4I9/2 (899 nm), 4F3/2→4I11/2 (1063 nm) and 4F3/2→4I13/2 (1338 nm) were observed in all glass matrices upon 532 nm laser excitation. Stimulated emission cross-section (σemi = 2.55 × 10-20 cm2) and effective line width (Δλeff = 28 nm) for the 4F3/2→4I11/2 transition in 1.0 mol% of Nd3+ doped TZN glass were compared with other reported glasses. Measured (τmeas) and calculated (τcal) of 4F3/2 level, quenching rates (kmeas) and quantum efficiencies (η) were also reported. The energy transfer mechanism has been discussed using spectral overlap (Forster-Dexter theory), Inokuti-Hirayama (IH) and Burshtein's hopping migration models, respectively.