二氧化硅光子晶体异质结构的制备与性质研究

Fabrication and Properties of Silica Photonic Crystal Heterostructures

利用垂直沉积技术制备了高质量的二氧化硅蛋白石结构和光子晶体异质结构,采用扫描电镜和光学透射谱进行了样品的结构表征。对同一样品不同区域的扫描电镜照片进行快速傅里叶变换分析,证实了胶体晶体的长程有序排列。通过对具有不同晶格常数的二氧化硅蛋白石结构的光学透射谱进行研究,提出光学透射谱中透射背景向短波长区域平滑的下降可能来自于结构缺陷散射的影响。与相应的蛋白石结构相比,光子晶体异质结构的光子禁带明显展宽,禁带深度也相对变浅,推测其来自于膜厚的影响。异质结构中各个光子禁带位置与蛋白石结构相比,并没有发生明显的移动。通过谱图对比研究,分析了光子禁带的叠加效应。

Silica opal structures and photonic crystal heterostructures are fabricated by vertical deposition technique.The structures of samples are characterized by scanning electron microscopy and optical transmission spectra.The long-range order of the silica opals is confirmed by fast Fourier transform analysis of scanning electron microscopy image at different region of the same sample.The smooth decline of background in the transmission spectra of different silica opals is attributed to the contribution of scattering from the structural defects.The photonic stop band of photonic crystal heterostructures exhibits obvious broadening and flattening in contrast to the corresponding silica opals,where the effect of film thickness is considered.The positions of photonic stop band show consistency between photonic crystal heterostructures and corresponding silica opal structures.The overlap of photonic stop band in heterostructures is discussed in detail.