Abstract: The present invention provides a method to control the degree of connectivity of the colloidal particles making up a colloidal crystal and, consequently, the pore size, filling fraction, mechanical stability and optical properties of the colloidal lattice, without disrupting its long range order and without the deleterious effects of lattice contraction induced cracking observed in conventional necking methods based on thermal sintering. The colloidal particles are connected to adjacent colloidal particles in the lattice by a homogeneous layer of uniform and controllable thickness of a metal oxide. This metal oxide layer is grown in a layer-by-layer process and is chemically bonded to the colloidal particle surface and serves to enhance the mechanical stability of the colloidal crystal in addition to acting to control the pore size or void volume between the colloidal particles in the lattice.

Abstract: This invention describes methods of synthesis and applications of planarized photonic crystals. Provided are simple, quick, reproducible and inexpensive methods that combine self-assembly and lithography to achieve the first examples of vectorial control of thickness, structure, area, topology, orientation and registry of colloidal crystals that have been patterned in substrates for use in lab-on-chip and photonic chip technologies. 1-, 2 and 3-D colloidal crystals patterned either on or within substrates can be used for templating inverted colloidal crystal replica patterns made of materials like silicon as well as building micron scale structural defects in such colloidal crystals.

Abstract: The invention described herein is broadly directed to 3D photonic crystal fibers exemplified but not limited to novel 3D inverse colloidal crystal fibers made of silicon. In particular the invention relates to the general utilization of controlled size and controlled shape and controlled length microchannel surface relief patterns that have been lithographically defined in silicon substrates for the geometrically confined crystallization of silica microspheres to form highly ordered and oriented colloidal photonic crystal microchannel templates and the utilization of such templates for creating, through silicon infiltration synthetic strategies, colloidal silicon-silica photonic crystal composite materials thereof and the subsequent removal of the silica template and detachment of these colloidal silicon-silica photonic crystal composite materials from the silicon substrate by etching in a fluoride-based medium to create oriented free standing 3D inverse colloidal photonic crystal fibers.

Abstract: A new type of synthetic silicon colloidal photonic colloidal crystal is described presenting a different topology than previously synthesised high refractive index contrast colloidal photonic crystals. It has been built using a new synthesis process based upon micromolding in inverse silica opals (MISO), where the micromold has a structure of interconnected air cavities in a silica matrix. By chemical vapour deposition of disilane within this micromold, a continuous and uniform silicon layer of controlled thickness is formed, which coats the walls of the silica matrix. Later, by dissolution of the starting silica micromold it is possible to obtain a face centered cubic silicon colloidal photonic crystal with a topology never observed before and which presents a full photonic band gap, as indicated by theoretical photonic band structure calculations making them useful as optical components of envisioned all-optical microphotonic crystal devices, circuits, chips and computers.