平行取向向列相液晶缺陷光子晶体透射谱

Photonic Crystal Transmission Spectrum with Parallel Alignment Nematic Liquid Crystal Defect

研究了平行取向向列相液晶缺陷多层介质膜一维光子晶体的透射谱特性。自然光垂直入射，光子禁带范围为518．5～582．0nm，并且禁带中观察到成对出现的透射峰。偏振光垂直入射，当偏振方向分别与液晶盒摩擦方向垂直、平行时，成对透射峰中的一个消失。而当入射光偏振方向与摩擦方向成45°时，光子禁带中仍出现了成对透射峰。由于液晶层具有折射率各向异性，光波存在两种本征模式（e模式和。模式）。入射光偏振方向与摩擦方向平行时为e模式，与摩擦方向垂直时为。模式，与摩擦方向成45°时两种模式共存。

Transmission spectral properties of one-dimensional multilayer photonic crystal infiltrated with a parallel nematic liquid crystal are investigated. The range of photonic band gap is 518.5 - 582.0 nm when natural light is incident vertically to the glass substrate and paired transmission peaks are observed in photonic band gap. One of the paired transmission peaks disappears in the case of adding a polarizer and making polarization direction parallel or perpendicular to rubbing direction with vertical incidence of polarized light. For an angle of 45° between polarization direction and rubbing direction, paired transmission still appears in photonic band gap. Optical wave has two eigenmodes （e- and o-mode） because of the anisotropy of liquid crystal layer. When the polarization direction of incident light is parallel to rubbing direction the optical wave is in e-mode, and when perpendicular to rubbing direction it is in o-mode. For the case of polarization direction and rubbing direction at an angle of 45°, two modes coexist.