二维正方各向异性碲圆柱光子晶体完全禁带中缺陷模的FDTD计算分析和设计

A FDTD method for calculating defect modes in a two-dimensional photonic crystal consisting of anisotropic cylinders

用FDTD方法计算了二维正方晶胞各向异性碲圆柱光子晶体的点缺陷模 .为了得到TE ,TM模式在完全禁带中具有相同共振频率的缺陷模 ,对中心点缺陷半径Rd 以及中心附近对称位置的点缺陷半径Rn 做了一系列微调 .计算表明 ,TM模对于Rn 的变化不敏感 ,而TE模随着Rn 的改变出现了明显的规则的移动趋势 .通过计算分析 ,发现对应于f=0 .4的背景 (R =0 .35 6 8a) ,当Rd=0 .5 5a ,Rn=0 .2 6a时在完全禁带中TE和TM的缺陷模具有相同的共振频率ω0 =0 .2 4 6 6ωe(其中ωe=2πc a ,a为晶格常数 )

A finite differece in time domain (FDTD) method is employed to calculate defect modes in a two-dimensional photonic crystal consisting of anisotropic cylinders of tellurium. In order to obtain a defect mode inside the complete band gap, we adjust the radius R-d of the central defect and radius R-n of the neighboring defects. It is shown that the defect modes for the E-polarization are not sensitive to R-n, while the resonance frequency for H-polarization varies regularly as R-n changes. When the filling fraction f = 0.4 (R = 0.3568 a), R-d = 0.55 a and R-n = 0.26 a, the defect mode has the same resonance frequency omega(0) = 0.2466omega(e) (where omega(e) = 2pic/a, a, c being lattice constants) for both E-and H-polarization.