Nanostructured photonic crystal properties

Electrochemical anodization of multi-layer AI/Ta/Al thin film compositions was developed to fabrieate regular nanostructures of tantalum oxide (TaiOs). Anodization kinetics, space characteristics of TaaOs nanopillars and electrical properties of Al/TaiOs/Al structures have been studied. Al/Ta/Al thin film compositions were shown to permit formation of regular nanostructured layers appropriate for photonic crystal and nanoelectronic applications. 

Symmetry Analogous to the crystalline lattice of atomic stmctures, photonic nanostructures may have different symmetries. According to the structural symmetry of photonic crystals, different scattering symmetries are caused, leading to a variation of the photonic band-gap properties. 

The properties of photonic crystals are strongly dependent on their structure and on the dielectric contrast between the different constituent materials. Often, one of these materials is the air in the cavities present in the ordered nanostructured medium. Filling these cavities with a proper material for its dielectric constant and photophysical properties opens intriguing perspectives in the photonic... 

Metal containing polyynes are multifunctional materials which combine the properties of organic polymers with those of metal centers coordinated to the organic moiety and are able to form nanotemplates, colloidal photonic crystals, multilayer capsules and hollow vesicles [127, 128], An example of a rod-like polymetallayne self-assembly in hollow nanorods has been recently reported [129] the computer simulations of the nanostructure show that the polymer chains are ordered in parallel lines that give rise to a tubular morphology rather unusual for these materials, but promising for sensor devices applications. 

The possibility of controlling the synthesis of a desired nanostructure opens a vast field of alternatives to design structures with definite optical responses. As already discussed, pore control of OMPOs allows the tuning of many refractive indices, which stacked strategically (periodically) result in ID photonic crystals. On the other hand, the pores of OMPOs can be implemented as nanoreactors for the growth of nanoparticles within them. The optical properties of combining both systems are not necessarily foreseeable, but probably respond to a... 

The photoelectrochemical properties of different semiconductor materials have been widely reported, for single crystal, polycrystalline, as well as for nanostructured materials. In the literature various methods for measuring the efficiency are found. The most common is the JPCE (incident photon-to-current conversion efficiency) or quantum efficiency, which is defined as... 

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