Site-selection spectroscopy and energy transfer studies of Eu3+ ions in a new fluorophosphate glass

The spectral migration of the time-resolved resonant line-narrowed D-5(0) --> F-7(0) emission band of Eu3+ in a new fluorophosphate glass of compositions (in mol%) 60NaPO(3)-15BaF(2)-(25-x)YF3-xEuF(3) (x = 0.5, 2, 5, 10, 15, 20, 25) has been investigated. The results may be interpreted in terms of a dipole-dipole energy transfer mechanism between the distributions of Eu3+ centers. Analysis of the measured fluorescence decays of the D-5(0) state suggest that the transfer process is Fast enough to drive the system of excited centers to thermal equilibrium.