Up-conversion Luminescence in Nanocrystalline Zirconia Co-doped with Yb3+ and Tm3+ Ions
LIU Huang-qing, QIN Guan-shi, LIN Hai-yan, WU Chang-feng, QIN Wei-ping, ZHANG Ji-sen, ZHAO Dan
Key Laboratory of Excited State Processes, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130022, China
Abstract：Nanocrystalline zirconia co-doped with Yb3+ and Tm3+ ions was prepared by co-precipitation. Up-conversion luminescence of the samples doped with different Tm3+ concentrations was investigated under a 980 nm LD excitation. When x=0.2 and 0.4, the luminescences of the two samples were mostly the same: strong blue up-conversion peaked at 474 nm and very weak red up-conversion were observed, corresponding to the transitions of 1G4→3H6 and 1G4→3F4 respectively. However, there was no luminescence of x=1. Blue up-conversion luminescence of 0.2 mol% Tm3+-ions-doped nanocrystalline zirconia under different annealing temperatures was investigated. Blue up-conversion emission grew stronger with annealing temperature increasing. With pumping current increasing, blue up-conversion emission grew stronger too. By studying the sources of blue up-conversion, we concluded that it was three-photon process.
