Kolloide: Neuartige Bausteine für Photonische Kristalle. Synthese, Bildungsmechanismus, Charakterisierung und Kristallisation von Hochindex-Partikeln

光子晶体是具有折射率的周期性变化的图案化材料，其产生被称为光子带隙的一系列禁止的光学频率。光子带隙从根本上改变了光的传播和发射过程。基于这些效应，可以设计出新型的集成光子材料，开辟了各种新的应用领域。光子晶体是由具有单模和双模球尺寸的高折射率胶体球构成的。为此，在第一步中，开发和优化单分散高折射率颗粒的合成。为了获得良好的单分散性，有必要对形成过程进行研究。在下一步中，颗粒将被精确地表征，因为折射率强烈地取决于颗粒的结构和组成。在最后一步中，胶体颗粒通过自组织或通过逐层方法结晶成新的胶体晶体。最后，将相似的高折射率粒子用于强无序样品中，以寻找起始光局域化。

Photonic crystals are materials patterned with a periodic variation of the refractive index creating a range of forbidden optical frequencies called a photonic band gap. A photonic band gap modifies fundamentally the propagation and emission processes of light. Based upon these effects novel integrated-photonic materials can be designed, opening various new areas of applications. Photonic crystals, composed of colliodal high index spheres with mono- and bimodal sphere size, should be synthesized. For that purpose in a first step the synthesis of monodisperse high index particles are developed and optimized. To achieve a good monodispersity investigations of the formation process are necessary. In a next step the particles will be exactly characterized, because the refractive index strongly depends on the structure and the composition of the particles. In a last step the colloidal particles are crystallized to novel colloidal crystals either by self-organization or by layer-by-layer method. Finally, the similar high index particles will be used in strongly disordered samples to search for the onset light localization.