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Opal Composites

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In order to expand the photonic crystal properties of artificial opals, and/or change their functionaity, high dielectric constant materials should be infiltrated in their pore lattice. See examples with

	The trivial: water
	Polymers
	Rhodamine 6G
	InP can be grown by CVD from metallorganic compounds
	ZnO is a material with extraordinary properties that can be grown in the framework of the opals by CVD.
	CdS where the degree of infiltration is monitored,
	Germanium grown by wet and CVD methods and
	Silicon where full photonic band gaps are obtained.
	Si and Ge layers forming shells around the spheres can be grown. For these synthesis methods high temperatures are needed which impedes the use of organic beads. To circumvent this an intermediate step of silica growth ca be employed that can lead to onion-layer opals.
	Antimony Sulfide The highest energy complete photonic band gap so far has been achieved with Sb2S3 inverted opals that were obtained either by CBD or sulfidation of antimony oxide.