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Photoconducting polymeric composites (PPCs) containing nanosized organic or inorganic dopants (dyes and their aggregates, nanoparticles of inorganic semiconductors) are already employed as photoactive media in OLEDs, in photoelectric solar energy converters, in optoelectronic elements, and in electrography and holography. The final application is the subject of this chapter. The basic requirements of holographic recording media (HRM) for the photothermoplastic (PTP) recording technique are considered. Features of the PTP recoding are described and the main demands to HRM are formulated: low electric conductivity, high photoconductivity at the light wavelength of the used laser, good film-forming, and optical and thermoplastic properties. The mechanisms of PPC photoconductivity are studied, including photogeneration, recombination, transport, and capture of nonequilibrium charge carriers. These mechanisms are particular to the organic and inorganic disordered nanomaterials with photosemiconducting properties and differ from the mechanisms in crystal materials due to the absence of long- and short-distance orders in the disordered nanomaterials. Possibilities for the development of new polymeric bases for PPC are discussed to provide a realization of the requirements for HRM. A comparison of the photophysical and information properties of HRM based on cooligomers with linear and radial structure is fulfilled similarly to investigations into the influence of nanoparticle size on the photophysical properties of semiconductor materials. The potentials for the improvement of the information characteristics of HRM is considered with concrete examples. “Wet” development of holograms is not required in the PTP holographic recording technique. Thus, this technique can be used not only in visual holography, but mainly, and more effectively, in holographic interferometry for nondestructive quality control, for detection of the residual stresses in metallic units, and for measurements of refractive index, etc. Concrete examples of HRM and devices for their application are described. This information is not only of scientific interest for widening knowledge about the photo processes in PPC, but is also useful for practical applications of photosemiconducting nanomaterials for quality control of the means of production and products, for prevention breakage, crashes, and catastrophes.

There have been two effects of the external electric field influence on the diffraction efficiency of reconstructed holograms observed in the films of copolymers 4-[(2-nitrophenyl)diazenyl]phenyl methacrylate with octylmethacrylate, when holographic recording of the plane wave front for parallel and orthogonal orientation of polarization vectors of light beams was performed at room temperature. After recording at exposure with small energies, diffraction efficiency in the electric field formed by corona discharge decreases, while with large exposure energies, it increases. Diffraction efficiency and recording velocity are higher in copolymer with lower softening temperature. The first effect is caused by reorientation of the dipole moments of azobenzene isomer fragments in the electric field, while the growth of diffraction efficiency is explained by the increase in the amplitude of regular geometric relief of the film surface, which appears during formation of the polarization hologram.

Thermal dependent changes of light depolarization degree were observed in the SnO2:In2O3 (ITO) layers deposited onto the flat glass substrates which are used usually as electrodes for optoelectronic devices. The observed effect is reversible. It can be attributed to the changes of nanostructure geometry in the bulk of the ITO layer as well as on its surface. Such geometric changes involve dispersion of polarized light. The investigated effect should be taken into consideration when developing optoelectronic devices because it can provoke distortion of the optical information field.