提出一种以Au为材料的正方形框和中空圆柱嵌套的亚波长周期性复合结构，采用时域有限差分算法对复合结构进行数值模拟研究。研究发现，波长在400~900 nm的线偏振平面波垂直入射情况下，最小的透过率能达到7.46%，最小的半峰全宽能达到7.25 nm，最大的反射率为87.61%，最大吸收率达到38.00%，且表现出透射光谱与入射光的偏振方向无关。分析发现，复合结构的共振模式由两基本结构的共振模式耦合而来，且嵌套模式可以进一步减小单一结构的透过率和增大光与复合结构的相互作用。通过改变复合结构参数，得到了较宽且高效的等离激元调控范围和较窄的透射光谱。这也为设计人工亚波长周期性复合结构的研究提供一定的理论指导。

A sub-wavelength periodic composite structure with square frame and hollow cylinder nested by Au is proposed. The finite difference time domain algorithm is used to simulate the composite structure. It is found that the minimum transmittance can reach 7.46%, the minimum full width at half maxima can reach 7.25 nm, the maximum reflectivity is 87.61%, and the maximum absorptivity is 38.00%, when the wavelength is 400?900 nm. It is found that the resonant mode of the composite structure is coupled by the resonant mode of the two basic structures, and the nested mode can further reduce the transmission of single structure and increase the interaction between light and composite structure. By changing the parameters of the composite structure, a wide and efficient control range of plasmon and a narrow transmission spectrum are obtained. This provides theoretical guidance for the design of artificial subwavelength periodic composite structures.