PREPARATION OF PHOTONIC CRYSTALS MADE OF AIR SPHERES IN TITANIA

Three-dimensional crystals of air spheres in titania (TiO2) with radii between 120 and 1000 nanometers were made by filling the Voids in art ificial opals by precipitation from a Liquid-phase chemical reaction a nd subsequently removing the original opal material by calcination. Th ese macroporous materials are a new class of photonic band gap crystal s for the optical spectrum. Scanning electron microscopy, Raman spectr oscopy, and optical microscopy confirm the quality of the samples, and optical reflectivity demonstrates that the crystals are strongly phot onic and near that needed to exhibit band gap behavior.