An Er³⁺/Yb³⁺ co-doped Ca₉Y(VO₄)₃(PO₄)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 ⁴I_13/2→⁴I_15/2 transition of Er³⁺ are 1.04 ×10⁻²⁰ and 0.8 × 10⁻²⁰ cm² 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 ⁴I_11/2 and ⁴I_13/2 multiplets of Er³⁺ in the crystal are 14.27 µs and 4.89 ms, respectively. The energy transfer efficiency from Yb³⁺ to Er³⁺ in the crystal was estimated to be about 69.3%.

中文翻译：

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Er3+/Yb3+共掺杂Ca9Y(VO4)3(PO4)4晶体的偏振光谱特性

Er ³⁺ /Yb ³⁺共掺杂Ca ₉ Y(VO ₄ ) ₃ (PO ₄ ) ₄晶体采用直拉法生长，并在室温下研究了该晶体的偏振光谱特性。对于σ和π，Er ³⁺的⁴ I _13/2 → ⁴ I _15/2跃迁的峰值发射截面在 1533 nm 处分别为1.04 ×10 ^-20和 0.8 × 10 ^-20 cm ²极化，分别。对于π偏振，在 1.55 µm 附近的发射带最大值的一半处的全宽约为 50 nm 。晶体中Er ³⁺的⁴ I _11/2和⁴ I _13/2多重_峰的荧光寿命分别为14.27 µs 和4.89 ms。晶体中从Yb ³⁺到Er ³⁺的能量转移效率估计为约69.3%。