Near-infrared downconversion through energy transfer from VO_4^3- group to Yb 3+ in Yb 3+ doped YP 0.9 V 0.1 O 4

Through the study of photoluminescence spectra, fluorescence decay curves, concentration-dependent luminescence and low temperature luminescence, the energy transfer from isolated VO_4^3- group to Yb 3+ is investigated in Yb 3+ doped YP 0.9 V 0.1 O 4 . The experimental results show that the energy transfer from VO_4^3- group to Yb 3+ is very efficient. Cooperative energy transfer, through which one high-energy photon absorbed by VO_4^3- group is converted to two near-infrared photons emitted by Yb 3+ ions, is proposed to be the energy transfer process. This efficient ultra-violet to near-infrared downconversion could have potential application in improving the efficiency of silicon-based solar cell.