Cooperative energy transfer in Eu3+, Yb3+ codoped Y2O3 phosphor

Under 980 nm laser excitation, red emission (5D0–7FJ (J=0, 1, 2)) of Eu3+ was observed in cubic Y2O3 codoped with Eu3+ and Yb3+. The dependence of the upconverted emission on doping concentration and laser power was studied. Yb3+ emission around 1000 nm (2F5/2–2F7/2) was reported upon excitation of Eu3+ ions. The decay curves of 5DJ (J=0, 2) emission of Eu3+ under excitation of 266 nm pulse laser were examined to investigate the Eu3+ → Yb3+ energy transfer process. Cooperative energy transfer process was discussed as the possible mechanism for the visible up-conversion luminescence of Eu3+ and near-infrared down-conversion emission of Yb3+.