Spectroscopic characterization of orthorhombic δ-BiB3O6 phase nonlinear single crystal doped with Pr3+ ions

The spectroscopic properties of 1 at% Pr3+ doped δ-BiB3O6 (BIBO) single crystal were investigated. The absorption, emission and excitation spectra were studied at low (10 K) and at room temperature, with the emission and absorption spectra showing clear polarization dependence. The strongest observed luminescence band corresponds to the 1D2 → 3H4 transition at 610 nm. Energy levels of Pr3+ in δ-BIBO host were assigned on the basis of low temperature absorption and emission measurements. The number of crystal field levels derived implies that Pr3+ ions are located in one crystal site in the BIBO host. Decay time of the praseodymium 3P0 emission was unusually short and the 1D2 decay was non-exponential. The modified Judd-Ofelt intensity formalism was used to analyze the experimental data. The Ωλ parameters, branching ratios and electric dipole transition probabilities were determined. The stimulated emission cross-sections σ for the 5D0 → 3HJ transitions were also evaluated in this system.