Er^(3+)掺杂锗酸盐激光玻璃发光特性的定量预测与分析

Quantitative prediction and analysis of luminescent properties in Er^(3+)-doped germanate glass

锗酸盐玻璃具有红外透过范围宽、最大声子能量低、机械性能优异等特点,是中红外窗口和固体激光器等的核心工作介质.以往在新玻璃体系研究中主要依赖“试错法”,这种方法基于大量实验,获得的数据有限.而常用的统计法、加和法等计算预测方法又仅局限于玻璃的物理性质计算,难以有效指导新型激光玻璃的探索.本文以Er^(3+)掺杂BaO-CaO-GeO_(2)(BCG)玻璃为例,提出利用该玻璃体系相图中的五种一致熔融化合物(CaO·GeO_(2),CaO·2GeO_(2),CaO·4GeO_(2),BaO·4GeO_(2)和BaO·GeO_(2))的物理和光谱性质,即可快速定量地预测整个玻璃形成区内所有玻璃组成的物理和光谱特性.研究表明,在该玻璃体系中,物理性质如密度和折射率的理论预测与实际值的最大误差分别为−2.05%和−0.97%,光谱特性如1530和2710 nm波段的有效线宽、吸收和发射截面、寿命、增益带宽和光学增益的最大误差均小于10%.在此基础上,建立了Er^(3+)掺杂BCG玻璃组成-结构-性质数据库,并将其初步应用于不同场景玻璃的成分设计.本研究符合玻璃结构相图模型的理论思想,对其他激光玻璃的研究具有指导意义.

Germanate glass is a core medium for midinfrared and solid-state laser because of its wide infrared transmission range, low maximum phonon energy,and excellent mechanical stability.In the past,the research on these new glasses relied on a large number of experiments to obtain limited data,and theoretical prediction methods,such as the addition method,were primarily limited to the calculation of physical properties,so it was difficult to effectively guide the exploration of new laser glasses.Taking Er^(3+)-doped BaOCaO-GeO_(2)(BCG)germanate laser glass as an example,this study used the physical and luminescent properties of five congruently melting compounds in the phase diagram(CaO·GeO_(2),CaO·2GeO_(2),CaO·4GeO_(2),BaO·4GeO_(2),and BaO·GeO_(2))to accurately and quantitatively predict those of all glass compositions in the entire glass-forming region.The results show that the maximum relative errors between the calculated and experimental density and refractive index values were−2.05%and−0.97%,respectively.The effective linewidth,absorption,and emission cross-sections,lifetime,gain bandwidth,and optical gain of luminescent properties at 1530 and 2710 nm were all less than 10%.On this foundation,a database of the composition,structure,and property of Er^(3+)-doped BCG glass was established,and it was initially applied to the composition design of glass for various purposes.This finding supports the theoretical idea of the phase diagram approach and has guiding significance for other laser glass research.