Nonradiative energy transfer and ion-ion interactions in terbium-praseodymium coactivated borate glass

Abstract

A study of energy transfer between Tb3+ and Pr3+ in borate glass is being presented. From our measurement of fluorescence emission and decay times of donor (Tb3+), in the presence of different concentrations of acceptor (Pr3+), the energy transfer probability (Pda) and transfer efficiency (ɳT) have been calculated. Analyzing the data it is observed that the non-radiative energy transfer in our borate glass system occurs by dipole-dipole interactions, contrary to the observations made by Nakazawa and Shionoya (dipole-quadrupole interaction) in phosphate glass. A linear dependence of Pda versus C at low acceptor concentration suggests the migration of excitation energy among donor ions before the energy is finally transferred to the acceptor ion. At high acceptor concentrations a plot of Pdavs (C0 + C)2; where C0 is donor concentration and C is the acceptor concentration, presents a linear dependence suggesting thereby that one donor interacts with two neighbouring acceptors consistent with Fong-Diestler mechanisms of dipole-dipole energy transfer interactions.