Growth, luminescence and energy transfer studies of Pr3+, Yb3+ co-doped CaYAlO4 single crystal

Pr3+, Yb3+ co-doped CaYAlO4 (Pr, Yb: CYA) single crystal was grown using the Czochralski (CZ) method. For near-infrared quantum-cutting system, a quantum efficiency of 145% for Pr3+, Yb3+-codoped CYA crystal has been obtained by ignoring the nonradiative losses. Under excitation at 940 nm, high intensities of 502 nm, 555 nm, 628 nm, 661 nm and 729 nm emissions turn up. Fluorescence decay time of 3P0→3F2 emission of Pr3+ ions and 2F5/2→2F7/2 transition of Yb3+ ions were also studied as evidences for energy transfer.