Upconversion emission from Tm3+:Yb3+ and Tm3+:Er3+:Yb3+ doped Y2SiO5 powders prepared by combustion synthesis

Tm3+:Er3+:Yb3+ doped Y2SiO5 powders were prepared by combustion synthesis with estimated as-prepared weight (wt.) % concentrations of 0.25:0.0:2.0, 0.25:0.5:2.0 and 0.25:1.0:2.0, respectively. Blue (Tm3+: 1G4 → 3H6), green (Er3+: 4S3/2, 2H11/2 → 4I15/2) and red (Er3+: 4F9/2 → 4I15/2) upconversion (UC) emissions were observed under 975 nm infrared diode laser excitation. The UC process took place via energy transfer from Yb3+ to Er3+ and Tm3+ ions. The CIE chromaticity coordinates of Tm3+:Er3+:Yb3+ doped Y2SiO5 powders were investigated as a function of the diode laser power and Er3+ concentration.