PbI_2对远红外Te基硫系玻璃光学性能的影响

摘要

用传统的熔融淬冷法制备了一系列新型Ge-Te-PbI2硫系玻璃,并且讨论了玻璃的形成区域.利用X射线衍射（XRD）、差热分析（DTA）、可见/近红外吸收光谱、红外透过光谱等技术,研究重金属卤化物PbI2对Ge-Te硫系玻璃组成、结构和性能的影响.利用Tauc方程计算了样品的直接和间接光学带隙,根据金属标准和能量带隙理论讨论了玻璃光学带隙与组分变化的关系.结果表明：PbI2的引入,提高了Te玻璃的形成能力,而且玻璃的热稳定性良好;随着PbI2含量的增加,玻璃的密度和折射率均增大,光学带隙减小,短波吸收截止边发生红移,玻璃的红外截止波长基本不变,达到了25μm.该系列玻璃可用于制备远红外长波波导器件.%A novel series of Ge-Te-PbI2 chalcogenide glasses is prepared by traditional melt-quenching method,and the glass-forming region is determined.X-ray diffraction,differential thermal analysis,visible/near-infrared absorption spectroscopy and infrared transmission spectra are adopted to analyze the composition,the structure,and the performance of the Te-based glasses system with an addition of PbI2.The Tauc equation is used to calculate the direct and the indirect optical band gaps,based on the metallization criterion and the band gap energy theory,the relationship between optical band gap and composition is investigated.The results show that with the addition of PbI2,the glasses-forming ability and the thermal stability are improved,Also,the density and the refractive index of glass sample both increase,the short-wavelength edges shift to ward a longer wavelength,the band gap decreases and the infrared cut-off wavelength of glass is 25μm which keeps almost unchanged.The series of glasses can be adopted to fabricate the far-IR optical wave—guide devices.