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Information × Registration Number 0215U001159, 0112U000561 , R & D reports Title Electromagnetics of layered composites with chiral properties and multifunctional planar systems popup.stage_title Head Shylga Sergey, Khardikov Vyacheslav, Registration Date 30-01-2015 Organization Kharkov National University named after V.N. Karazin popup.description2 Object of research is a physical process of formation of scattering fields during the interaction of monochromatic and/or pulsed electromagnetic radiation of local or non-local sources with two-dimensional planar periodic structures or finite sequence of layers of complex composition that may have chiral properties. The work aim is to improve consumer characteristics and increase the competitiveness of the control devices in the optical, infrared, millimeter and centimeter ranges, as well as determination of phenomena of field formation by the thin planar structures and finite sequence of anisotropic, chiral layers with various parameters and geometry structure and their dependence on operating conditions. Mapped pseudospectral time domain method and auxiliary differential equation method with complex pole model for describing of frequency dependence of permittivity were used for numerical studying of two-dimensional planar structures. Analysis of periodic sequences was based on the method of circuit theory and matrix functions. The mathematical model of photonic crystals based on the sequence of layers of chiral medium, that taking into account the effects of nonreciprocity and the possible effect of chiral-nihility medium, was developed in the project. This mathematical model based on the analysis of eigen waves of infinite layered media and scattering fields of finite sequences, including the presence of a defect in the structure. The conditions of exciting and increasing of cross-polarized component in scattering fields were determined. The mathematical model of optical metasurfaces, that support of high-Q trapped mode resonances, was developed in the project. The possibility of creating all-dielectric metasurfaces supporting resonance in trapped mode, based on semiconductors was shown for the first time. Exciting conditions and physical properties of the trapped mode resonances were determined. These effects and numerical and analytical algorithms developed in the work are the basis for developing of multifunctional devices of electromagnetic field control with unique characteristics in microwave, infrared and optical ranges. Obtained in the work results prove the relevance of further research as layered structures and metasurfaces in trapped mode resonance regime. It is primarily about using nonlinear and active media as a defect in the periodic sequence of layers, or as substrate of metasurfaces. The polarization transformation effects in layered structure of the chiral and biisotropic layers, that were studied in the work, and their dependence on the angle of incidence and chiral and nonrecipricity parameters can significantly extend the functionality of microwave and optical devices. The data obtained during research can be used to design artificial media with unique parameters, filters, selective and high-impedance surfaces, antenna radomes, components of optoelectronic communications, laser mirrors, bistable elements etc. Product Description popup.authors Іванченко Д. Антюфеева М. Багацька О. Биков В. Грідіна В. Демченко О. Туз В. popup.nrat_date 2020-04-02 Close