Fig. 1. Up-conversion emission spectra of Er³⁺/Yb³⁺ co-doped Ba₅Gd₈Zn₄O₂₁ phosphor under 1550 nm laser excitation. Inset picture shows the luminescence intensity of No. 1 sample and the optimal sample for comparison. Er³⁺/Yb³⁺共掺Ba₅Gd₈Zn₄O₂₁在1550 nm激光激发下的上转换发射光谱(插图为1号样品与最优样品的发光强度对比)

Fig. 2. Up-conversion emission spectra of Er³⁺/Yb³⁺ co-doped Ba₅Gd₈Zn₄O₂₁ phosphor under 980 nm laser excitation. Inset picture shows the luminescence intensity of No. 3 sample and the optimal sample for comparison. Er³⁺/Yb³⁺共掺Ba₅Gd₈Zn₄O₂₁在980 nm激光激发下的上转换发射光谱(插图为3号样品与最优样品的发光强度对比)

Fig. 3. XRD patterns of samples, and standard peaks of Ba₈Gd₅Zn₄O₂₁ (JCPDS No.51-1686) are included for comparison. 样品的XRD与标准卡片JCPDS No.51-1686图样

Fig. 4. Dependence of the integrated intensity of up-conversion luminescence on laser working current.上转换发光强度积分与激光器工作电流的依赖关系

Fig. 5. Dependence of red up-conversion luminescence intensity on temperature under (a) 980 nm and (b) 1550 nm excitation for optimal samples.最优样品在(a) 980 nm与(b) 1550 nm激光激发下的红色上转换发光强度随温度的变化

Fig. 6. Dependence of red up-conversion luminescence intensity compared with commercial phosphor of NaYF₄ under (a), (b) 980 nm and (c), (d) 1550 nm excitation for optimal samples. 在(a), (b) 980 nm和(c), (d) 1550 nm激光激发下最优样品与NaYF₄商品粉末发光强度的比较

Fig. 7. The Multiple ratio of red up-conversion luminescence intensity compared with commercial phosphor of NaYF₄ under 980 nm and 1550 nm excitation for optimal samples. 在980 nm和1550 nm激光激发下最优样品与NaYF₄商品粉末发光强度的倍数比

Fig. 8. Comparison of red up-conversion luminescence intensity of optimal samples at the same power density.相同功率密度下最优样品的红光上转换发光强度比较