Nanostructured photonic crystals

Schwartz MP, Derfus AM, Alvarez SD, Bhatia SN, Sailor MJ (2006) The smart Petri dish a nanostructured photonic crystal for real-time monitoring of living cells. Langmuir 22(16) 7084-7090... 

Liquid Crystal Optical Slab Waveguide, Fiber, and Nanostructured Photonic Crystals... 

These ordered array materials find interest not only in catalysis, but in several other applications, from optical materials, sensors, low-k materials, ionic conductors, photonic crystals, and bio-mimetic materials.Flowever, with respect to these applications, catalysis requires additional specific characteristics, such as the presence of a thermally stable nanostructure, the minimization of grain boundaries where side reactions may occur, and the presence of a porous structure which guarantees a high surface area coupled to low heat and mass transfer limitations. An ordered assembly of ID nanostructures for oxide materials could, in principle, meet these different requirements. 

Another nice example of nanostructuring an MIP layer is the work published by Wu et al. [138, 139] who developed a label-free optical sensor based on molecularly imprinted photonic polymers. Photonic crystals were prepared by self-assembly of silica nanospheres. The space between the spheres was then filled with MIP precursor solution. After polymerization, the silica was dissolved, leaving an MIP in the form of a 3D-ordered interconnected macroporous inverse polymer opal (Fig. 15). The authors were able to detect traces of the herbicide atrazine at low concentrations in aqueous solution [139]. Analyte adsorption into the binding sites resulted in a change in Bragg diffraction of the polymer characterized by a color modification (Fig. 15). 

At the top of systems proposed for processors of quantum computers, there are systems in which electronic and nuclear spins of various defects and impurities in diamond are used as stationary qubits [1,2]. Single NV-centers having electronic spin S=1 in the ground electronic state are the most promising [3]. To improve optical read-out of such spin-states, various three-dimensional nanostructures in diamond such as micro resonators, waveguides, photon-crystal structures, etc. [1,4,5] are being developed. Besides, the methods of NV-center... 

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. 

In conclusion, it was confirmed that anodization process for multi-layer Al/Ta/Al thin film structure differs considerably from that for two-layer composition. The developed technique permits to produce regular nanostructured layers of various compositions. Formation of nanostructured layers based on anodic Ta, Ti, Nb and A1 oxides using multistep anodic oxidation and simultaneous control of their geometrical characteristics will permit to create fimctional layers for specific applications, in particular for photonic crystals, photoelectrochemical cells, electrochromic displays. 

Tessier PM, Velev OD, Kalambm- AT, Rabolt JF, Lenhoff AM, Kaler EW (2000) Assembly of gold nanostructured films templated by colloidal crystals and use in surface-enhanced Raman spectroscopy. J Am Chem Soc 122 9554 Yan H, Blanford CF, Holland BT, Parent M, Smyrl WH, Stein A (1999) A chemical synthesis of periodic macroporous NiO and metallic Ni. Adv Mater 11 1003 Von Freymann G, John S, Schulz-Dobrick M, Vekris E, Tetreault N, Wong S, Kitaev V, Ozin GA (2004) Tungsten inverse opals The influence of absorption on the photonic band structure in the visible spectral region. Appl Phys Lett 84 224 Denny NR, Han SE, Norris DJ, Stein A (2007) Effects of thermal processes on the structure of monolithic tungsten and tungsten alloy photonic crystals. Chem Mater 19 4563... 

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. 

As mentioned earlier, colloidal photonic crystal devices were fabricated through a self-assembly process. This process is the most economic method to produce 3D nanostructures. When the size of a colloidal building block is half the wavelength of visible light, a physical change of the photonic crystals caused by the analytes converts into a color change. However, the width of the reflectance peak is usually broad, which disturbs the high sensitive characterization. 

Velev, O. D., P. M. Tessier, A. M. Lenhoff, and E. W. Kaler. 1999. Nanostructured photonic metal synthesized via colloidal crystal templates. Nature 401 548. 

Mclnnes S, Voelcker N (2012) Porous silicon-based nanostructured microparticles as degradable supports for solid-phase synthesis and release of oligonucleotides. Nanoscale Res Lett 7(1) 1-10 Mclnnes SJP, Szili EJ, Al-Bataineh SA, Xu J, Alf ME, Gleason KK, Short RD, Voelcker NH (2012) Combination of iCVD and porous silicon for the development of a controlled drug delivery system. ACS Appl Mater Interfaces 4(7) 3566-3574 Meade SO, Yoon MS, Ahn KH, Sailor MJ (2004) Porous silicon photonic crystals as encoded microcarriers. Adv Mater 16(20) 1811-1814... 

Recio-Sanchez G, Torres-Costa V, Manso-Silvan M, Martin-Palma RJ (2012) Nanostructured Porous Silicon Photonic Crystal for Applications in the Infi-ared. J Nanotechnol 2012 (106170) l-6.doi 10.1155/2012/106170... 

Wehrspohn RB (ed) (1995) Chapter 7, Macroporous silicon photonic crystals. In Ordered porous nanostructures and applications. Springer, New York Wehrspohn RB, Schilling J (2003) A model system for photonic crystals macroporous silicon. Phys Stat Solid (a) 197 673-687... 

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