Abstract
We discuss a method for fabricating photonic crystals of closely packed air spheres with diameters on the order of 300 nm in a rutile titania matrix. These differ from the air sphere/titania materials reported elsewhere in that the matrix is the high-index rutile phase of titania (n≈2.9) as opposed to the low-index anatase phase (n≈2.4). We make these materials by a sol-gel process with oil-in-formamide emulsions as templates. The emulsion droplets are stable and have a polydispersity of 15% or less, allowing them to form small colloidal crystallites when concentrated in a titania sol. The oil template can be removed after gelation of the sol and prior to drying, allowing us to produce monolithic samples with few cracks. Calcination at 1000 °C converts the structure to the rutile phase with an average crystallite size of 60 nm. Optical transmission spectra show the presence of a broad minimum at a wavelength of 500 nm for a sample with ordered 200 nm pores.
Original language | English (US) |
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Title of host publication | Proceedings of SPIE - The International Society for Optical Engineering |
Publisher | Society of Photo-Optical Instrumentation Engineers |
Pages | 44-50 |
Number of pages | 7 |
Volume | 3937 |
State | Published - 2000 |
Event | Micro- and Nano-Photonic Materials and Devices - San Jose, CA, USA Duration: Jan 27 2000 → Jan 28 2000 |
Other
Other | Micro- and Nano-Photonic Materials and Devices |
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City | San Jose, CA, USA |
Period | 1/27/00 → 1/28/00 |
ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Condensed Matter Physics