中文摘要：

采用平面波展开法研究了2D三角晶格空气孔型光子晶体的带隙结构和空气环型光子晶体的完全带隙。结果发现空气孔半径R从0.41a到0.49a之间变化时,空气孔型的完全带隙会越大;在同一空气孔半径（R=0.41a~0.47a）下空气环型结构都能得到比空气孔结构更宽的完全带隙,得到最优参数R=0.47a,r=0.133a下的完全带隙为0.1698THz,是空气孔结构的1.15倍。使用时域有限差分法研究了空气环型结构的透射谱,根据计算结果设计了（0.7198~0.8655）THz波段的滤波器。

英文摘要：

Band gap of 2D triangular lattice photonic crystal with circular air holes and ring-shaped air holes in THz range was studied by using plane wave expansion method （PWM）. It was found that complete band gap of circular holes was larger when the holes radius increased from 0.41a to 0.49a. For the same hole radius, ring-shaped holes photonic crystal could get the larger complete band gap than circular holes, and the optimal parameter was 0.169 8 THz when the holes radius of 0.47a, inner radius of 0.133a, was 1.15 times for circular holes structure. Transmission spectrum of ring-shaped holes photonic crystal was studied by finite-difference time-domain method （FDTD）, and we designed the filter in （0.7198 ~0.865 5） THz wave.