Polymer composites with azobenzene dyes and their metallic complexes are considered as perspective media for polarization holography [1,2]. This holographic technique has many unique properties and possibilities as compared to the scalar holography. These ones result in advantages of polarization holographic information storage and in more flexible opportunities of light beam control when using light polarization sensitive photoactive media. There is considerable interest in the synthesis and characterization of azobenzene-containing polymers because of their potential applications in photonic fields [3,4]. When irradiated with linearly polarized light the long molecular axis of the azobenzene will be aligned perpendicular to the electric field vector of the polarized actinic light through photochemical trans–cis–trans isomerization cycles. This process results in optical anisotropy, which can be monitored by the photoinduced birefringence measurements. Because of their unique properties, the polymers with azobenzene chromophores are expected to be one of the most attractive materials for reversible optical data storage media. However, most of the investigations focused on the single azobenzene-based polymers. The films of copolymer octyl methacrylate with incorporated azo dyes and its complex with Co were synthesized and investigated in the present work. Two azo groups in the bisazobenzene derivatives can undergo photoisomerization and consequently orientation under illumination with polarized light, which may increase the efficiency of photoalignment and lead to novel optical properties. Presence of metallic ions opens additional possibilities for control the electric, magnetic and optical properties of these polymer composites, especially by external electric and/or magnetic field. Physical mechanisms of formation of optical anisotropy in these media under influence of polarized light are described. Experimental investigations of recording of the hologram of flat wave front in new polymeric composites with azobenzene polycomplexes with coordinated metallic ions are done. Conclusion about potential applicability of this medium for polarization holography is made. References: [1] Todorov, T.; Nikolova, L.; Tomova, N. In: Appl.Opt., 1984, 23, 4309. [2] Yang, Q.; Wei, Z.; Zhang, Y.; Sun, G.; Li, F. In: Appl.Phys.B, 2001, 72, 855. [3] Camorani, P.; Cristofolini, L.; Fontana, M.P.; Angiolini, L. In: Mol.Cryst.&Liq.Cryst., 2009, 500, 1. [4] Ishitobi, H.; Tanbe, M. In: Optics Express, 2007, 15, 652.
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