Photonics polymer liquid crystal

Tondiglia, V., Natarajan, L., Sutherland, R. et al.. Holographic formation of electro-optical polymer-liquid crystal photonic crystals, Adv. Mater., 14, 187, 2002. 

Tondiglia, V.P., et al.. Holographic Formation of Electro-Optical Polymer-Liquid Crystal Photonic Crystals. Advanced Materials, 2002.14(3) p. 187-191. 

Yagi R, Katae H, Kuwahara Y, Kim SN, Ogata T, Kurihara S. On-off switching properties of onedimensional photonic crystals consisting of azo-functionalized polymer liquid crystals having different methylene spacers and polyvinyl alcohol. Polymer 2014 55 1120-7. 

Polymer-dispersed liquid crystals were introduced many years ago. There are now several techniques for preparing such composite liquid crystalline materials, including the phase separation and the encapsulation methods.More recently, optical holographic interference methods have been employed successfully in making polymer-dispersed liquid crystal photonic crystals (regular array of materials of different refractive indices). Caputo et al. and Strangi et al. have also demonstrated one-dimensional (ID) polymer/liquid crystal layered structures that exhibit high diffraction efficiency as well as laser emission capabilities. 

In this chapter we will review the recent advances of supramolecular photon chirogenesis in various confined media, excluding micelles, chiral solvents, liquid crystals, metal complexes, polymer matrices, clays, and crystals. Micelles are typical supramolecular assembly with an internal hydrophobic core which shows a unique boundary effect, e.g., enhanced radical recombination of geminate radi-cal pairs produced by ketone photolysis [26], but essentially no asymmetric photon-... 

K. Ueno, N. Hirano, O. Tsutsumi, T. Shiono and T. Ikeda, Liquid-crystalline materials for photonics Effect of glass transition on stability of optical image stored in polymer azobenzene liquid crystals, Polym. Prepr., Jpn., 1995, 44, 1820. 

From Table 2.3, which lists typical // values, it can be seen that the hole mobility in conjugated polymers is lower than that in organic crystals and amorphous silicon, but much larger than that in undoped poly(N-vinyl carbazole). Therefore, conjugated polymers have potential for applications in conducting opto-electronic and photonic devices. In principle, this also applies to liquid-crystal systems that can exhibit enhanced molecular order due to their self-organizing ability, as has been pointed out in a progress report [42]. 

Electrochromism is a phenomenon displayed by some materials reversibly changing colors. Various materials can be used to construct electrochromic devices, such as transition metal oxides, liquid crystals, photonic crystals, and polymers (Booth and Casey, 2009 Nicoletta et al., 2005 Arsenault et al., 2007 Gamier et al., 1983). Here, we will focus on the electrochromic materials based on polymers. There are several mechanisms to explain the color changes of polymer electrochromic materials like electro-induced oxidation-reduction and electrothermal chromatic transition and so on. 

The photoluminescence of polyaniline has been studied as a function of the polymer redox state. It was stated that each of the three PANI species have fluorescent emissions with different quantum yields. When conductive domains are present, the emission fi-om excitons located either inside these domains or near to them is efficiently quenched [40], Organic electroluminescent devices (LED s) are a possible alternative to liquid crystal displays and cathodic tubes, especially for the development of large displays. The principal setup for a polymeric LED is ITO/light-emitting polymer/metal. A thin ITO electrode on a transparent glass or polymeric substrate serves as the anode, while metals such as Al, Ca or Mg are used as cathode materials. After applying an electric field, electrons and holes are injected into the polymer. The formation of e /h" " pairs leads to the emission of photons. One of most important opportunities to follow from the use of poly-... 

J. Yan, L. Rao, M. Jiao, et al.. Polymer-stabilized optically isotropic liquid crystals for next-generation display and photonic applications, J. Mater. Chem. 21, 7870-7877 (2011). 

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