Bright upconversion white light emission in transparent glass ceramic embedding Tm3+∕Er3+∕Yb3+:β-YF3 nanocrystals

Abstract

Intense red (Er3+:F9∕24→I15∕24, Tm3+:G41→F43), green (Er3+:H11∕22, S3∕24→I15∕24), and blue (Tm3+:D21→F43, G41→H63) upconversion emissions were simultaneously generated in the transparent glass ceramics containing Tm3+∕Er3+∕Yb3+:β-YF3 nanocrystals under single 976nm laser excitation. It was demonstrated that Tm3+ behaves as the sensitizer for red luminescence of Er3+ and Er3+ as the quenching center for blue, red, and near-infrared upconversion emissions of Tm3+. 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.