Lin Hua, Chen Hong, Zheng Yu-Jun, Yu Ju-Song, Wu Xin-Tao, Wu Li-Ming
State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian, 350002, P. R. China.
University of Chinese Academy of Sciences, Beijing, 100039, P. R. China.
Chemistry. 2017 Aug 1;23(43):10407-10412. doi: 10.1002/chem.201701679. Epub 2017 Jul 13.
Mid-infrared (MIR, 2-20 μm) second-order nonlinear optical (NLO) materials with outstanding performances are of great importance in laser science and technology. However, the enormous challenge to design and synthesize an excellent MIR NLO material lies in achieving simultaneously a strong second harmonic generation (SHG) response [d >0.6 × AgGaS (AGS)] and wide band gap (E >3.5 eV). Herein three new MIR NLO materials, AZn Ga S (A=K, Rb, Cs) are reported, which crystallize in the KCd Ga S -type structure and adopt a 3D diamond-like framework (DLF) consisting of MS (M=Zn/Ga) tetrahedra; achieving the desired balance with strong powder SHG response (1.2-1.4 × AGS) and wide band gap (E ≈3.65 eV). Moreover, they also show large laser induced damage thresholds (LIDTs, 36 × AGS), a wide range of optical transparency (0.4-25 μm) and ultrahigh thermal stability (up to 1400 K). Upon analyzing the structure-property relationship of AX X Q family, these 3D DLF structures can be used as a highly versatile and tunable platform for designing excellent MIR NLO materials.
具有优异性能的中红外（MIR，2 - 20μm）二阶非线性光学（NLO）材料在激光科学与技术领域具有重要意义。然而，设计和合成一种优异的MIR NLO材料面临的巨大挑战在于要同时实现强二次谐波产生（SHG）响应[d > 0.6×AgGaS（AGS）]和宽带隙（E > 3.5 eV）。在此，报道了三种新型MIR NLO材料AZnGaS（A = K、Rb、Cs），它们结晶为KCdGaS型结构，并采用由MS（M = Zn/Ga）四面体组成的三维类金刚石框架（DLF）；在强粉末SHG响应（1.2 - 1.4×AGS）和宽带隙（E≈3.65 eV）之间实现了所需的平衡。此外，它们还表现出大的激光诱导损伤阈值（LIDTs，36×AGS）、宽的光学透明范围（0.4 - 25μm）和超高的热稳定性（高达1400 K）。通过分析AXXQ族的结构 - 性能关系，这些三维DLF结构可作为设计优异MIR NLO材料的高度通用且可调谐的平台。
