氟化物对Er3+/Yb3+共掺的碲酸盐玻璃上转换和红外发光性能的影响

Er³⁺/Yb³⁺ 共掺的碲酸盐玻璃由于其良好的上转换发光性能而得到广泛的研究。本文将氟化物引入碲酸盐玻璃中，通过熔融法制备了量比为70TeO₂-（30-x）ZnO-xZnF₂-0.15Er₂O₃-1.5Yb₂O₃（x=0，5，10，15，20）的碲酸盐氧氟玻璃样品，并测试其热稳定性、拉曼光谱以及受激发射光谱。实验结果表明，随着氟化物含量的提高，Er³⁺离子的410，555，670 nm上转换发光和2~3 μm波段中红外发光得到增强，并且红光提高强度比绿光和蓝光更明显。在分析了氟离子引入后对上转换与近中红外波段发光的内在影响机制发现：碲酸盐玻璃系统中的氟化物一方面促进能量传递过程中Er³⁺离子的双光子吸收，促进粒子跃迁至相应的高能级；另一方面，引入氟化物后的碲酸盐玻璃的最大能量声子态密度下降也是降低无辐射跃迁概率、提高上转换和中红外发射强度的重要原因。

Effect of Fluoride on Up-conversion and Infrared Luminescence Properties of Er3+/Yb3+ Co-doped Tellurite Glass

Erbium (Ⅲ)/ytterbium (Ⅲ)-codoped tellurite glass has been widely studied due to its good quality of up-conversion emission. In this work, fluoride was introduced in the tellurite glass and a series of glasses 70TeO₂-(30-x)ZnO-xZnF₂-0.15Er₂O₃-1.5Yb₂O₃(x=0, 5, 10, 15, 20, molar ratio) were prepared via melting process. The thermal stabilities were tested by DTA-TG, and the Raman spectra and stimulated emission spectra were obtained. The results show that the up-conversion luminescence of 410, 555, 670 nm and mid-infrared emission in the range of 2~3 μm are enhanced with the increasing fluoride content, and the red light at 670 nm get more greatly enhanced. We analyzed the intrinsic impact mechanism of fluoride ions on the up-conversion and infrared luminescence and drew the following conclusions: fluoride in tellurite glass could promote the two-photon absorption process of erbium ions, thereby promoting the particles transition to appropriate high-energy level; on the other hand, the maximum phonon density of glass decreased with the introduction of fluoride, which reduced non-radiative transition probabilities and thus improved the conversion and mid-infrared emission intensity.