摘要：光子晶体表面波是光子晶体研究的重要方向，我们通过改变光子晶体出射端界面上介质柱的半径大小，使用时域有限差分方法计算发现在光子带隙内存在共振峰，我们计算了这一共振频率对应的场分布，通过场分布局域在出光子晶体出射端表面这一特性，我们证明了改变光子晶体出射端界面上介质柱的半径可以在光子晶体的表面支持表面波的存在。同时，我们还研究了表面波的共振频率随着光子晶体出射端表层介质柱半径的变化关系以及表面波存在的介质柱的半径范围。这些研究结果对设计基于表面波的光子晶体器件有着重要的意义。

关键词：光子晶体； 时域有限差分； 表面波 

Abstract: Photonic crystal surface wave is an important research direction. In this paper, we change the radius of the interface layer of photonic crystal and use FDTD as our numerical method. By numerical study, we find a resonant peak within the photonic bandgap. We calculate the field distribution of this resonant frequency and find that the optical field is localized at the interface layer. This proves that the photonic crystal could support surface waves when changing the radius of the interface layer. We also study the relation between the frequency of surface wave and the radius of interface layer. These results have important applications in designing surface wave based photonic crystal devices.

Key words：Photonic crystal；Finite-difference time-domain；Surface wave