Energy transfer dynamics of Er 3+ /Nd 3+ embedded SiO 2 -Al 2 O 3 -Na 2 CO 3 -SrF 2 -CaF 2 glasses for optical communications

Abstract The fluorescence and upconversion studies of Er 3+ doped and Er 3+ /Nd 3+ co-doped silicate based oxyfluoride glasses have been systematically analyzed. The broad band NIR emissions (830–1700 nm), includes optical bands like O, E, S, C and L were observed in the Er 3+ -Nd 3+ co-doped glasses. The NIR emission intensity peaks centered at 876, 1057, 1329 and 1534 nm were observed for the Er 3+ -Nd 3+ co-doped glasses. In the co-doped samples the strongest emission intensity at 1534 nm increased up to 0.5 mol % and then decreased to 3.0 mol % of Nd 3+ ions under the excitation of 980 nm. The upconversion studies of the co-doped samples were recorded under the excitation of 980 and 808 nm and found the upconversion emission peaks centered at 524, 530, 547, 590 and 656 nm. The energy transfer processes between the relevant excitation levels of Er 3+ and Nd 3+ ions and energy transfer efficiency were discussed. The obtained results indicate that Nd 3+ can be an efficient sensitizer for Er 3+ to enhance upconversion emission at green laser transition for sensors and NIR emission at 1534 nm for optical communication applications.