标题：New infrared nonlinear optical crystal CsGeBr3: Synthesis, structure and powder second-harmonic generation properties
作者：Tang, L.C. ;Huang, J.Y. ;Chang, C.S. ;Lee, M.H. ;Liu, L.Q.
作者机构：[Tang, L.C. ;Huang, J.Y. ;Chang, C.S. ] Department of Photonics, Institute of Electro-Optical Engineering, National Chiao Tung University, Hsinchu 305 更多
来源：Journal of Physics Condensed Matter
摘要：An innovative infrared nonlinear optical crystal CsGeBr3 was synthesized. Ab initio calculations on CsGeBr3 were also carried out in order to analyse the second-order nonlinear susceptibilities. From its powder x-ray diffraction pattern, this crystal was characterized as a rhombohedral structure with an (R3m, No 160) space group symmetry. The reflection powder second-harmonic generation (PSHG) measurement of CGBr showed that its nonlinear optical efficiency is 1.62 times larger than that of rhombohedral CsGeCl3 and is 9.63 times larger than that of KH 2PO4 (KDP), and most important of all that CsGeBr 3 is phase-matchable. The rescaled deff(2) of CGBr was about 2.45 times larger than that of rhombohedral CsGeCl3, and this trend was coincident with the ab initio calculation results. The infrared transparent spectrum of rhombohedral CsGeBr3 was extended to more than 22.5 νm. The rhombohedral CsGeBr3 shows the potential in the realm of nonlinear optics and can be applied to the infrared region. © 2005 IOP Publishing Ltd.