Three-dimensional Photonic Bandgap Crystals Of Titania Hollow Spheres At Visible Wavelengths

摘要

A non-close-packed three-dimensional photonic crystal of titania hollow spheres has been fabricated. The fabricated process is based on the silica template technique, thermal sintering, and the sol-gel process. The band-structure calculations and optical measurements both indicate that a quasi-full three-dimensional photonic bandgap located at the visible wavelength has been presented between the eighth and ninth bands. This indicates that the non-close-packed structure of titania hollow spheres was easier to open the complete photonic bandgaps than other face-centered cubic structures made by self-assembling methods at the visible region.