Polarized spectroscopic properties of Er3+/Yb3+ co-doped Ca9Y(VO4)3(PO4)4 crystal

An Er 3+ /Yb 3+ co-doped Ca 9 Y(VO 4 ) 3 (PO 4 ) 4 crystal was grown by the Czochralski method and the polarized spectroscopic properties of the crystal were investigated at room temperature. The peak emission cross sections of the 4 I 13/2 → 4 I 15/2 transition of Er 3+ are 1.04 ×10 −20 and 0.8 × 10 −20 cm 2 at 1533 nm for σ and π polarizations, respectively. The full width at half the maximum of the emission band around 1.55 µm is about 50 nm for π polarization. The fluorescence lifetimes of the 4 I 11/2 and 4 I 13/2 multiplets of Er 3+ in the crystal are 14.27 µs and 4.89 ms, respectively. The energy transfer efficiency from Yb 3+ to Er 3+ in the crystal was estimated to be about 69.3%.