中文摘要：

基于Smith—Purcell（SP）效应，采用粒子模拟的方法探讨了电子束团激发一维介质光子晶体中的SP辐射特性．模拟研究了单个束团激发一维介质圆柱光子晶体产生的SP辐射现象，并对周期束团激发的THz频段的相干SP辐射进行了模拟分析．研究表明，提高介质的相对介电常数和增加光子晶体的层数都可使辐射强度增加，选择合适的参数能够有效地增强THz频段的相干SP辐射强度．

英文摘要：

This paper presents a study of Smith - Purcell （SP） radiation properties with the particle - in - cell （PIC） simulation. The model supposes one - dimension （1D） dielectric cylindrical photonic crystal driven by a single electron bunch and a train of periodic bunches, respectively. The results show that the radiation from a single electron bunch is enhanced by increasing the dielectric constant and layers of the photonic crystal. The terahertz （THz） coherent SP radia- tion is obtained by exciting the photonic crystal with periodic electron bunches. The coherent radiation strength is im- proved by choosing proper operating parameters.