Fabrication photonic crystals

Another important method for photonic crystal fabrication employs colloidal particle self-assembly. A colloidal system consists of two separate phases a dispersed phase and a continuous phase (dispersion medium). The dispersed phase particles are small solid nanoparticles with a typical size of 1-1000 nanometers. Colloidal crystals are three-dimensional periodic lattices assembled from monodispersed spherical colloids. The opals are a natural example of colloidal photonic crystals that diffract light in the visible and near-infrared (IR) spectral regions due to periodic modulation of the refractive index between the ordered monodispersed silica spheres and the surrounding matrix. 

R(0H)3 do not provide many applications themselves, though there are some reports on tribology (Zhang et al., 1998, 2001a), sensing (Liu and Song, 2006), and photonic crystal fabricated with monodisperse silica shell (Lin et al., 2007b). 

Subramania, G. et al.. Optical photonic crystals fabricated from colloidal systems, Appl. Phys. Lett., 74, 3933, 1999. 

LARGE OPTICAL ANISOTROPY OF ID PHOTONIC CRYSTAL FABRICATED BY VERTICAL ETCHING OF SILICON... 

When two materials of differing refractive indices are extruded into a nanolayer structure that has an effective layer thickness of approximately 1/4 the wavelength of visible light, the material is effectively a ID visible photonic crystal. The nano-layer extrusion process is a continuous process that yields photonic crystals that are flexible sheets of a polymer. This is a great advantage since it can easily and rapidly produce photonic materials with a much larger size than typical photonic crystal fabrication techniques. 

Astrova EV, Tolmachev VA, Fedulova GV, Melnikov VA, Ankudinov AV, Perova TS (2010) Optical properties of one-dimensional photonic crystals fabricated by photo-electrochemical etching of silicon. Appl Phys A 98 571-581... 

Most of the 3D photonic crystals fabricated via solution-based approaches are inverted opals, since the fabrication of inverse-opal photonic crystals and the evaluation of their optical properties both are relatively simple and easy. There have been a large number of studies that dealt with opal and inverse-opal photonic crystals in the literature, and it is impossible to cover most of the contents of the studies reporting inverse-opal (and opal) photonic crystals concerning their fabrication processes, characterization of the crystals, optical properties, and applications (Chen, 1999 Sun, 2000a Muller, 2000 McComb, 2001 Stein, 2001 Scroden, 2001 Astratov, 2002). Therefore, the contents of only a few of such studies as dealt with metal oxide inverted opals fabricated by the sol-gel process are presented here. 

Waterhouse, G.l.N. and Waterland, M.R. (2007) Opal and inverse opal photonic crystals fabrication and characterization. Polyhedron, 26, 356-368. 

Divliansky, Ivan, and Theresa S. Mayer. 2006. Three-dimensional low-index-contrast photonic crystals fabricated using a tunable beam sphtter. Nanotechnology. 17 1241-1244. 

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