Near-infrared quantum cutting in YPO4:Yb3+, Tm3+ via cooperative energy transfer

The experimental evidences of the cooperative energy transfer from Tm3+ to Yb3+ have been presented by the photoluminescence properties of YPO4:Yb3+, Tm3+, and the decay lifetime curves of the G14 emission of Tm3+. Near-infrared quantum cutting involving the F25/2→F27/2 emission of Yb3+ (about 970–1010 nm) is achieved upon the excitation of G14 energy level of Tm3+ at 474 nm. Quantum efficiency related to Yb3+ concentration is calculated, and the maximum efficiency reaches 172.8%. Because the energy of Yb3+ transition is matched with the band gap of the crystalline Si, the phosphors could be applied potentially in silicon-based solar cells.