Optical properties photonic crystals

The use of multi-layer systems as a preform for microdrawing allows for the production of glass elements with new optical properties [122,123] which may find apphcations in optical filters and interference devices. The most common apphcation of drawn elements, however, is in fibre optics and photonic crystals [52,292,432]. 

A second kind of electronic defect involves the electron. Let us suppose that the second plane of the cubic lattice has a vacancy instead of a substitutional impurity of differing valency. This makes it possible for the lattice to capture and localize an extraneous electron at the vacancy site. This is shown in the following diagram. The captured electron then endows the solid structure with special optical properties since it ean absorb photon energy. The strueture thus becomes optically active. That is, it absorbs light within a well-defined band and is called a "color-center" since it imparts a specific color to the crystal. 

Painter O., Srinivasan, K., O Brien, J.D., Scherer, A., and Dapkus, P.D., 2001, Tailoring of the resonant mode properties of optical nanocavities in two-dimensional photonic crystal slab waveguides, J. Opt A Pure Appl. Opt. 3 S161-S170. 

Colloidal crysfals can be viewed as the mesoscopic counterpart of atomic or molecular crystals. They have been used to explore diverse phenomena such as crystal growth [52-54] and glass transition [55,56], and have many interesting applications for sensors [57], in catalysis [58,59], advanced coatings [60], and for optical/electro-optical devices for information processing and storage [61,62]. In particular, their unusual optical properties, namely the diffraction of visible light and the existence of a photonic stop band, make them ideal candidates for the development of photonic materials [61,63-66]. They may lead to the fabrication... 

Sakoda K. Optical Properties of Photonic Crystals, Springer Vedag. Inc., New York, NY, 2001. 

Recently, a second-order nonlinear photonic crystal has been realized.38 In this nonlinear optical bandgap material, there is a periodicity in the nonlinear optical properties of the engineered material. With this definition, a periodically poled second-order nonlinear optical material could be called a nonlinear photonic crystal. However, its linear optical properties do not show a periodicity, except for the (small and useless for bireffingent phase-matching) poling-induced birefringence. Here, the material is the same in the complete structure. It is only periodically made into a non-centrosymmetric structure for second-order nonlinear and phase-matching... 

It is believed that nonlinear optical photonic crystals, which can bend and amplify elected photons (wavelengths) of light, will dominant signal-processing technology after the electronics era. This, combined with the intriguing properties of matter at the nanoscale, has made nano-optics an active research held. 

Following the discovery of ordered mesoporous materials, the templated approach was also employed for the synthesis of ordered macroporons materials. Macroporous materials with nniform pore sizes are predicted to have useful optical properties and may have applications as photonic crystals with optical band gaps. ... 

It is important to have a strong understanding of the effects of processing on the optical properties of a material or structure. In this case, we look to understand how structure affects properties and how processing affects structure one then can decide the best approach for preparing a photonic crystal with a desired performance. 

Vlasov, Y, Astratov, V, Baryshev, A. et al.. Manifestation of intrinsic defects in optical properties of self-organized opal photonic crystals, Phys. Rev. E, 61, 5784, 2000. 

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