Study of emission and optical interaction in the UO2–Nd system doped in zinc phosphate glass

Abstract

The study of the interaction between optically excited ions that enhances emission from fluorescence cations can be useful in industrial application and scientific research. The sensitization of active rare earth ions by uranyl ion can be particularly useful for improving the pumping efficiency of solid-state lasers. Keeping the above facts in mind, non-radiative energy transfer from optically excited UO2++ to Nd3+ has been studied in zinc phosphate glass by keeping donor concentration fixed and varying acceptor concentration at room temperature. From the experimental investigation, it has been observed that the emission intensity of the donor (UO2++) decreases with increasing acceptor (Nd3+) concentration resulting in a non-radiative energy transfer from UO2++ to Nd3+. According to Fong–Diestler’s and Forster and Dexter’s theories, the dipole–dipole transfer mechanism is found to be dominant in the present system and phonon-assisted energy transfer is also suggested. At different acceptor concentrations, various parameters necessary for the quantitative study, e.g., donor–acceptor distances (DD→A), transfer efficiencies (η), energy transfer probabilities (Pda) and critical transfer distances (R0), have been calculated. In the present study, we report that uranyl ion is particularly useful as an indirect pumping source for Nd3+.