A study on energy transfer and energy migration models for RE ions luminescence system

By Application of the V-F-B model which is obtained by combining the Vasque z-Flint (V-F) model for donor-acceptor energy transfer and the model of Bur shtein for donor-donor energy migration, the experimental luminescence deca y curves of S-4(3/2) state of Er3+ in LaF3 at 295K for four different conce ntrations are re-simulated successfully. It is found that in this system th e donor-acceptor interaction is dipole-dipole interaction,and that the dono r-acceptor interaction constant C-DA is 4.75 X 10(-41) cm(6)/s. The results are all in agreement with the previous results of Okamoto. However, the ho pping time tau (0) obtained from the above simulation in proportional to x( D)(-1.237)(x(D) is the donor concentration), which is different from the th eoretical dependence on the donor concentration (that is tau (0)proportiona l tox(D)(-2)). In addition, by considering donor-acceptor energy transfer a nd donor-donor energy migration within the V-F model at the same time, we o btain the estimated values of the hopping time tau (0)' for four different concentrations, which are in reasonable agreement with the values of tau (0 ) obtained from the above simulation. It seems that the V-F-B model is rath er self-consistent.