镜像对称的光子晶体透射带特性

Transmission band characteristics of photonic crystals with mirror symmetry

通过传输矩阵方法计算了镜像对称光子晶体的带隙结构，结果表明该结构具有优越的窄带滤波性能．如果在该光子晶体两端均加入较高的折射率介质，构成夹心“三明治”结构，这时的光子晶体透射带结构出现多通道滤波特性；当两端加入不同的较高折射率介质但其光学厚度仍保持为基本结构单元的光学厚度时，得到宽度为50～2500nm大范围的低透射区．其具有宽带阻波作用；当两端加入的不同高折射率介质但光学厚度变为基本光学厚度的两倍时，则得到在中心波长处出现非常窄的完全透射峰，这种带隙结构可用来设计优异理想窄带滤波器．

Band gap structures of photonic crystals with mirror symmetry are calculated by using transfer matrix method. The results indicate that transmission band structure has a narrow bandwidth filtering characteristic. If two dielectrics with identical refractive index and the same optical thickness as the basic structure unit of photonic crystals are added at both ends of the photonic crystals ,then the band structure appears some narrow transmission peaks; While the two dielectrics with different refractive indexes and the same optical thickness as the basic structure unit are added at both ends,a broad-band filter for stopping light wave is obtained in the range of 50-2 500 nm;When the two dielectrics with different refractive indexes and the optical thickness as twice as the basic structure unit are added,a super narrow transmission peak inside the large band-gap can been found. This is ideal capability for designing excellent light wave filter.