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Information × Registration Number 0224U002096, 0122U001656 , R & D reports Title Study of features of forming and control of electromagnetic field state in cluster and/or topological metasurfaces popup.stage_title Head Khardikov Viacheslav V., Кандидат фізико-математичних наук Registration Date 06-02-2024 Organization V.N. Karazin Kharkiv National University popup.description2  The object of research is gain and nonlinear metasurfaces and their components. The subject of the study is origin and pecularities of the resonant phenomena in metasurfaces, including trapped mode resonances, and the effect on them of the gain or nonlinearity of the environment and metasurface elements. The purpose of the work is to develop methods and mathematical models for revealing and studying the laws of control of the state of the electromagnetic field in cluster and/or topological metasurfaces; analysis of physical effects in these systems and search for optimal parameters for their practical application. Research methods are diffraction theory methods, in particular the finite element method. Results: the exsisting conditions of exceptional points in the hybrid dielectric waveguide-"spacer" structure were revealed, and it was shown for the first time that the degeneracy of the eigenmodes of the system components is removed in the region of these points, the possibility of two-factor control of the position of the exceptional points was revealed. It is shown that the use of a cluster formed by a trimmer of identical disks as base of gain metasurface allows to significantly expand its functionality, in particular, such a metasurface allows to obtain photoluminescence amplification in a wide range of values, to form a system with several almost monochromatic peaks of radiation, which will also have a predominant polarization. A model of a non-linear silicon metasurface was built and the possibility of achieving non-reciprocal reflection of light into the first diffraction beam was demonstrated for the first time, i.e. the phenomenon of non-reciprocal non-specular reflection was achieved. For the first time, the effect of the metasurface elements anisotropy on its resonance properties was studied and it was shown that the anisotropy allows controlling such phenomena as the removal of modes degeneracy and the excitation of the trapped mode resonances. Product Description popup.authors Bagatska Olga V. Prosvirnin Serhiy L. Tomson Nataliia V. Tuz Volodymyr R. Fesenko Volodymyr I. Khardikovа July A. popup.nrat_date 2024-02-06 Close