Preparation And Optical Properties Of A Cylindrical Three-dimensional Photonic Crystals

Photonic crystals are periodic optical nanostructures. Because of this kind of structure they have the photonic band gap, and it can be used to make optical switch, optical filter, chemical and biological sensors and so on. In recent years, the inverse opals cause more attention because that they can form complete photonic band gap. In this paper I focous my research on the fabrication of opals and inverse opals on the inner surface of capillaries, also do some research about their optical properties and the formation mechanism of monodispersed microspheres self-assembly. These studies provide a certain theoretical and experimental basis for the fabrication of three-dimensional microstructure optical fiber. Therefore, the fabrication of cylindrical opals and inverse opals has a certain research significance and application value.In this paper, we study the theory and experiment technology of the fabrication of inverse opals by the sol-gel co-assembly method. We do some simulation about the transmission spectrum and reflectance spectrum of inverse opals by EastFDTD software, and we find the influence of the number of layers of crystals with base to the the band gap position. Then we fabricate the inverse opals by the sol-gel co-assembly method. With different particle size of PS microspheres are fabricated. And by comparing the experiments we discuss some parameters, such as:the volume ratio of the PS colloidal suspension and hydrolyzed TEOS solution, sintering temperature curve,which may has influence on the quality of SiO2inverse opals.In this paper, we also research the fabrication of photonic crystals on the curved surface. First we fabricate the hollow cylindrical PS photonic crystals by vertical deposition method on the inner surface of capillaries, and fabricate the hollow cylindrical SiO2inverse opals by sol-gel co-assembly method. Then we fabricate cylindrical solid opals and inverse opals with gravity sedimentation method, and by analysing the SEM and its spectrum we can know that the produced photonic crystals is highly ordered. At the same time, the mechanism as well as the assembly process of monodispersed microspheres self-assembly in a capillary have been investigated. Finally we find that substrate curvature radius and microspheres size are main factors affect the quality of hollow opals and inverse opals.