Bright upconversion white light emission in transparent glass ceramic embedding Tm~(3+)/Er~(3+)/Yb~(3+):β-YF_3 nanocrystals

摘要

Intense red (Er~(3+):~4F_(9/2)→~4I_(15/2), Tm~(3+): ~1G_4→~3F_4), green (Er~(3+):~2H_(11/2), ~4S_(3/2)→~4I_(15/2)), and blue (Tm~(3+): ~1D_2→~3F_4, ~1G_4→~3H_6) upconversion emissions were simultaneously generated in the transparent glass ceramics containing Tm~(3+)/Er~(3+)/Yb~(3+):β-YF_3 nanocrystals under single 976 nm laser excitation. It was demonstrated that Tm~(3+) behaves as the sensitizer for red luminescence of Er~(3+) and Er~(3+) as the quenching center for blue, red, and near-infrared upconversion emissions of Tm~(3+). Various colors of the luminescence, including perfect and bright white light with CIE-X=0.310 and CIE-Y=0.358, can be easily tuned by adjusting the concentrations of the rare earth ions in the material.