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The influence of bulk superconducting substrates and coatings on the domain structure parameters of a ferromagnetic ultra-thin film was analysed, assuming the validity of the London equation in the superconducting volumes. The problem was analysed for both easy plane and perpendicular easy axis films; however, as the effects of the superconducting substrate are relatively unimportant for films magnetized in plane, most of the article is devoted to easy axis films. Expressions for the demagnetization energy were found for arbitrary magnetization distribution. It was shown that a superconducting substrate changes the domain structure properties even if the layer is coated with a non-superconducting material. For sufficiently thin films the domain structure can be fully suppressed, which was shown by considering an isolated Bloch wall for larger anisotropy (Q > 1) and the critical domain structure for low anisotropy (Q < 1). The results of numerical calculations for critical ferromagnetic film thickness (as a function of anisotropy and London penetration depth) are presented.

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.