Photonic Crystals from Coated Colloids

三维光子晶体（包括胶体晶体和反蛋白石）将由新型涂层胶体（即核-壳）构建块制备，这些构建块提供了晶体光学特性的精确可调性。核壳胶体将通过各种聚电解质的逐层吸附以及预制的无机纳米颗粒来构建。这种策略将允许独立控制壳的厚度和组成。几种方法将检查构建高度有序的三维光子晶体，包括沉淀，离心，电泳沉积。随后从所涂胶体中去除所述核心产生空心颗粒；这些粒子的光子晶体也将以类似的方式构建。这些粒子的优点是它们提供了增加的折射率对比度，这是一个完整阻带必不可少的参数。将这些新颖且定义良好的胶体实体创建三维组合将产生具有独特和定制光子特性的光子晶体。

Three-dimensional photonic crystals (both colloidal crystals and inverse opals) are to be prepared from novel coated colloid (i.e. core-shell) building blocks that afford precise tunability of the optical characteristics of the crystals. The coreshell colloids will be constructed by the layer-by-layer adsorption of various polyelectrolytes as well as preformed inorganic nanoparticles. This strategy will allow independent control over shell thickness and composition. Serval methods will be examined to construct highly ordered three-dimensional photonic crystals, including sedimentation, centrifugation, and electrophoretic deposition. Subsequent removal of the core from the coated colloids yields hollow particles; photonic crystals of these particles will also be constructed in a similar fashion. The advantage of these particles is that they provide an increased refractive index contrast, a parameter essential for a complete stopband. Creating three-dimensional assemblies of these novel and well-defined colloidal entities will yield photonic crystals with unique and tailored photonic properties.