为了了解电磁波在2维三角晶格SiO₂/Si光子晶体的传输特性,利用时域有限差分方法进行了数值模拟和计算,并研究了SiO₂介质柱的形状和入射波模式的变化对晶体透射特性的影响。计算后得到多种情况下该光子晶体的透射率与入射光频率的关系曲线。结果表明,禁带的宽度和位置与构成光子晶体中SiO₂的形状有关,SiO₂柱半径变大则禁带变宽且禁带中心频率变大,半径为0.4a时,禁带宽度达到最大值。与TM模相比,TE模入射时,光子晶体更易形成禁带。这为光子晶体的实验制作和应用提供了理论依据。

The finite difference time domain method was used to simulate the transmission characteristics of 2-D triangular lattices SiO₂/Si photonic crystal.Furthermore,it was also studied how the change of the shape of SiO₂ and the mode of incident wave affect transmission properties of photonic crystal.The curves of transmissivity versus frequency of the incident wave in the different conditions were obtained.The calculated results obviously show that the band gap width and position are related to the shape of SiO₂ in photonic crystal.With the increase of the radius of SiO₂ cylinder,the band gap is widened and the central frequency is enhanced,but the largest band gap appears when R=0.4a.Compared with TM wave,the band gap appears more easily under the TE wave.The study provides the theory basis of the manufacture and application of photonic crystal.