Effect of inter-ionic interaction on photoluminescence property of yttriumaluminate garnet phosphors

The photoluminescence of Terbium-activated yttrium aluminate with the gener al formula Y3-XTbXAl5O12 was investigated as a function of Tb3+ concentrati on. The main attention is focused on the D-5(3)/D-5(4) fluorescence and its energy transfer behavior. The emission and excitation spectra were measure d in terms of Tb3+ concentration and analyzed in view of the application fo r plasma display panel (PDP). Also, the diffuse reflectance spectra were me asured and analyzed in the range from VUV to UV. As a result, the yttrium a luminate was found to have a broad excitation band extending from VUV to UV range and to show the typical concentration quenching behaviors both for D -5(3) and D-5(4) fluorescence. The energy transfer was investigated by anal yzing the decay curve of D-5(3) and D-5(4) emission based on the multipolar interaction or the exchange interaction. The decay curves of D-5(3) emissi on, for which well known cross relaxation has been accepted as a main facto r, were analyzed by Inokuti and Hirayama's formula based on the direct quen ching scheme. The decay curves of D-5(4) emission were analyzed by Yokota a nd Tanimoto's formula based on the diffusion limited quenching scheme. (C) 2001 Kluwer Academic Publishers.