本文研究一种利用金属光栅结构激发表面等离子体，实现增强非线性二次谐波激发效率的方法。通过设计金属光栅周期、沟槽深度等结构参数，使其满足推导出的准相位匹配条件，实现泵浦光与倍频光的表面等离子体模式同时共振激发，得到高效输出的倍频光。文中利用时域有限差分方法对该方法进行了模拟仿真，验证了准相位匹配条件和共振激发表面等离子体模式对提高二次谐波输出的关键性作用，同时分析了光栅结构参数变化对二次谐波激发效率的影响规律。

A metallic grating structure which can enhance Second-harmonic Generation (SHG) based on exciting Surface Plasmons (SP) is studied. By designing the structure parameters of the metallic grating with quasi phase matching condition, the SP of the fundamental mode and the second-harmonic mode can be excited simultaneously, which considerably enhance the efficiency of SHG emission. Numerical simulation for SHG behaviors of designed structures were performed by using the Finite Difference-time Domain Method (FDTD) and the results showed that the quasi-phase-match condition and the excited SP mode made a key role for enhancing the efficiency of SHG. Moreover, the effect of the structure parameters of the metallic grating on SHG emission was analyzed.