Mechanisms and concentrations dependence of up-conversion luminescence in Tm3+/Yb3+ codoped oxyfluoride glass-ceramics

The up-conversion properties of Tm3+/Yb3+ codoped oxyfluoride glass-ceramics under 980 nm excitation were investigated. Intense blue up-conversion luminescence due to the Tm3+: 1G4 → 3H6 transition was observed in the glass-ceramics. The intensity of the blue up-conversion luminescence in a 1 mol% YbF3-containing glass-ceramic was found to be about 40 times stronger than that in the precursor oxyfluoride glass. The up-conversion mechanism is proposed. The reason for the intense Tm3+ up-conversion luminescence in the oxyfluoride glass-ceramics and the concentrations dependence of upconversion luminescence are also discussed.