OPTICAL CHARACTERIZATION OF Eu3+ AND Tb3+ IONS DOPED ZINC LITHIUM BOROTELLURITE GLASSES

This paper reports on the development and spectral results of Eu3+ and Tb3+ ions doped zinc lithium boro tellurite glasses in the following composition: 20TeO(2) - (60-x) B2O3 -10 ZnO-10Li(2)O-x Eu2O3 20TeO(2) - (60-x) B2O3 -10 ZnO-10Li(2)O-x Tb4O7 (where x= 0.125, 0.25, 0.375, 0.5, 0.625 mol %) The measured emission spectrum of Eu3+ glass have revealed five transitions (D-5(0) -> F-7(0), F-7(1), F-7(2), F-7(3) & F-7(4)) at 578 nm, 592 nm, 612 nm, 643 nm, 701 nm respectively with lambda(exci)=392 nm (F-7(0) -> L-5(6)).In the case of Tb3+ glasses four emission transitions such as (D-5(4) -> F-7(6), F-7(5),F-7(4) & F-7(3)) that are located at 488 nm, 543 nm, 583 nm and 614nm respectively have been measured with lambda(exci)=376 nm. For all these emission bands decay curves have been plotted to evaluate their life times.