Emission and excitation characteristics and internal quantum efficiencies of vacuum-ultraviolet excited Pr3+-doped fluoride compounds -: art. no. 165112

We report on the spectroscopic investigation of Pr3+-doped binary, ternary, and quaternary fluoride compounds exhibiting photon cascade emission. Under vacuum-ultraviolet synchrotron excitation at wavelengths below 200 nm in the 4f5d bands of the Pr3+ ion the emission spectra show intraconfigurational 4f-4f transitions originating from the S-1(0) and P-3(0) multiplets. In the ternary and quaternary compounds investigated, i.e., Ca-, Sr-, Ba-, and Rb-fluorides, broadband emission due to transitions from the 4f5d level of Pr3+ are also observed. The different types of emission transitions observed in the compounds investigated were analyzed in detail. The internal quantum efficiency for the visible spectral range (390 nm-750 nm), eta(vis), is determined with the help of the Judd-Ofelt theory and the branching ratios of the S-1(0) emission transitions. The dependence of this quantum efficiency eta(vis) from the ionic radius of the second cation (R-2nd), the effective ligand distance, and the coordination number is investigated.