一种锗酸盐中红外非线性光学晶体的合成及性能研究

Synthesis and Properties Study of a Germanate Mid-Infrared Nonlinear Optical Crystal

本研究在锗酸盐体系引入含孤对电子和重元素的[PbOX]多面体,通过高温固相法合成了一种中红外非线性光学晶体——PbSrGeO4。该化合物结晶于非中心对称空间群P212121 (No. 19),具有优良的热稳定性(1066℃)。光谱分析显示PbSrGeO4的紫外截止边位于293 nm左右,红外截止边约为6.0 μm,在0.293~6.0 μm范围内具有良好的透过特性,可覆盖3~5 μm波段的关键大气透过窗口。粉末倍频测试结果表明,PbSrGeO4表现出适中的二次谐波响应(0.3 × KDP)。此外,本研究进一步探讨了PbSrGeO4微观结构与光学性能之间的内在关系。该研究提供了一种潜在的锗酸盐中红外非线性光学晶体,为设计探索新型锗酸盐中红外非线性光学材料提供了有益参考。

In this study, a [PbOX] polyhedra containing lone pair electrons and heavy elements was introduced to the germanate system, and a mid-infrared nonlinear optical crystal, PbSrGeO4, was synthesized through high-temperature solid-state method. The compound crystallizes in the acentric space group P212121 (No. 19) and exhibits excellent thermal stability (1066˚C). Spectral analysis reveals that the ultraviolet cutoff edge of PbSrGeO4 is around 293 nm, while the infrared cutoff edge is around 6.0 μm. It demonstrates good transmittance characteristics in the range of 0.293~6.0 μm, effectively covering the key atmospheric windows of the 3~5 μm region. Second harmonic generation tests indicate that PbSrGeO4 exhibits moderate second harmonic response (0.3 × KDP) and can achieve phase matching. Furthermore, this study explores the intrinsic relationship between the microstructure of PbSrGeO4 and its optical properties. The research provides a potential mid-infrared nonlinear optical crystal in the germanate system, offering valuable insights for the design and exploration of novel germanate mid-infrared nonlinear optical materials.