粉末倍频系数的模拟研究

根据Kurtz粉末倍频理论，使用光纤光谱仪自行设计搭建一个粉末倍频测试系统，该系统可在基频光波入射方向不变的情况下，通过转动旋转臂在不同方向探测二次谐波，并且具有较高的精确度和灵敏度。使具有位相匹配特性的颗粒尺寸范围扩大为46μm～250μm 。使用波长为1.064μm的基频光，对KIO3晶体粉末的倍频效应进行了测试。测试结果表明，KIO3晶体粉末透射倍频光具有位相匹配特性。这一测试结果与已报道结果相一致。通过数值模拟实验测试曲线，获得了KIO3晶体粉末的倍频系数d2ω的值为9.7×10-12m/V。这一模拟值与已报道的KIO3晶体对该基频光波产生的倍频系数d32的值相吻合。由此可见，该方法切实可行。并且可推广应用到其他晶体材料的非线性特性测试研究。

Simulation on powder nonlinear coefficients

Based on the Kurtz theory, a measurement system of powder second-harmonic (SHG) using fiber spectrometer was designed. The test system can measure SHG in different directions by rotating the arm and not changing-direction of incident fundamental light. It has good accuracy and sensitivity. It enlarges phase-matching particles from 46μm to 250μm. The fundamental wavelength of 1.064μm was used to measure KIO3 crystal powder SHG. The test result shows that KIO3 crystal powder has the phase-matching characteristics, which is consistent with the previous reports. The nonlinear coefficient d2ω of KIO3 crystal powder obtained by simulating the experimental curve is 9.7×10-12m/V. The simulation value agrees with d32 of KIO3 crystal reported previously. This method is proved feasible and could be used in the study of nonlinear characteristics for other crystal materials.