Up- and Downconversion Luminescence Properties of Nd3+ Ions Doped in Bi2O3-BaO-B2O3 Glass System

Abstract

Physical, optical, and luminescence properties of Nd3+ ions in bismuth barium borate glass system were studied. The glasses prepared by a melt quenching method were doped at various Nd2O3 concentrations in compositions (40-x)B2O3 : 40Bi(2)O(3) : 20BaO : xNd(2)O(3) (where x = 0.00, 0.50, 1.00, 1.50, 2.00, and 2.50 in mol%). Luminescence properties of the glasses were studied under two excitations of 585 and 750 nm for downconversion. From both excitations, the results show emission bands in NIR region corresponding to the transitions between F-4(3/2) -> I-4(9/2) (900 nm), F-4(3/2) -> I-4(11/2) (1,060 nm), and F-4(3/2) -> I-4(13/2) (1,345 nm). The luminescence intensity obtained with 585nm excitation was stronger than 750 nm, with the strongest NIR emission at 1,060 nm. The upconversion emission spectrum exhibits strong fluorescence bands in the UV region at 394 nm (lambda(ex) = 591 nm). The processes are associated with excited state absorption (ESA) from F-4(3/2) level to D-4(3/2) level and it is the radiative decay from the D-4(3/2) to ground levels (D-4(3/2) -> I-4(13/2)) which are responsible for the emission at 394 nm.