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Information × Registration Number 0225U002217, (0122U001663) , R & D reports Title Interaction of terahertz radiation with electron beams in hyperbolic and gyrotropic magnetophotonic structures popup.stage_title Підвищення ефективності генераторів та підсилювачів терагерцового діапазону із застосуванням модифікованих сповільнювальних систем. Head Smatko Oleksandr O., Доктор фізико-математичних наук Registration Date 25-02-2025 Organization V.N. Karazin Kharkiv National University popup.description1 Development of theoretical and conceptual bases for the creation of the novel sources of terahertz radiation using electrodynamic systems based on hyperbolic and gyrotropic metamaterials. popup.description2  The interaction of electromagnetic radiation with a 1D magnetophotonic crystal, the structure of which consists of dielectric layers and layers characterized by hyperbolic dispersion, has been studied. The dispersion equation for such a crystal has been obtained and the main characteristics of the eigenmodes, which are due to the existence of bulk and surface waves, have been determined. Analytical relations for the transmission coefficient of a magnetophotonic crystal have been obtained based on the Floquet-Bloch waves method. In the transmission zones of a multilayer periodic structure, which correspond to surface waves, high-Q resonance peaks are realized, characterized by almost complete energy transmission through the magnetophotonic crystal. These peaks are separated from each other by additional forbidden zones, which makes it possible to form effective narrow-band filters for controlling THz radiation. Modes of layered superconductors of cylindrical configuration have been studied. An expression for the frequency of nonlinear oscillations was obtained, which takes into account the small additive quadraticity of the oscillation amplitude and the effect of generation of the third harmonic of oscillations. It was found that the presence of small losses in the medium leads to a decrease in the amplitude of the extraordinary wave during its propagation and, ultimately, to the phenomenon of stopping THz waves. Several configurations of controlled 2D photonic crystal waveguides with hollow channels were investigated, which can be used as electrodynamic systems of THz electron devices. The elements of the waveguide claddings are gyrotropic, which allows controlling their operational characteristics by changing the external magnetic field. The proposed scheme of the electrodynamic system of a THz device allows developing compact beam-wave systems that do not require focusing fields and are controlled by external fields. Product Description popup.authors Averkov Yurii O. Apostolov Stanislav S. Kadyhrob Dmytro V. Kazanko Oleksandr V. Lysytsia Viktor T. Mizernik Viktoriya M. Odarenko Yevhen M. Pazynin Vadym L. Yampolskyi Valerii O. popup.nrat_date 2025-02-25 Close