Energy transfer between Tb3+ ions in YAlO3 host

The present investigation aims at elucidating the photoluminescence behavior of Tb3+ activated yttrium aluminate perovskite (YAP) phosphors. The attention is especially focused on the D-5(3) fluorescence and its energy transfer behavior. The decay curves of D-5(3) emission were measured in terms to Tb3+ content. Emission and excitation spectra as well as diffuse reflectance spectra were measured in the range spanning from vacuum ultraviolet (VUV) to UV. The energy tranfer between Tb3+ ions was also investigated by analyzing the decay curves of D-5(3) emission based not only on the multipolar interaction (dipole-dipole) but also on the exchange interaction. The rate equation including the contribution of 5d level was also proposed, which takes two different types of nonlinear terms into consideration. One is a well-known term designating the cross relaxation from D-5(3) to D-5(4) level, while the other square term represents the second type of cross relaxation from D-5(4) to D-7 level. (C) 2000 The Electrochemical Society. S0013-4651(00)03-116-5. All rights reserved.