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Information × Registration Number 0225U004307, (0123U102709) , R & D reports Title Optically and acoustically controlled devices based on crystalline and nanocomposite materials for modulation of terahertz radiation popup.stage_title Вимірювання раманівських спектрів створених кристалічних нанокомпозитів та розрахунок динаміки ґратки кристалів Bi12GeO20 та Bi12SiO20. Створення макетів модуляторів ТГц випромінювання та їх дослідження. Розробка акустично-керованого модулятора ТГц випромінювання на основі кристалів Bi12GeO20 чи Bi12SiO20. Head Andrushchak Anatolii S., Доктор технічних наук Registration Date 28-11-2025 Organization Lviv Polytechnic National University popup.description1 The aim of the project is to study the effect of optically designed diffraction gratings and electrophysical parameters of semiconductor substrates on the parameters of optically controlled terahertz modulator, as well as the effect on modulation of this radiation when controlling electron density waves due to surface acoustic waves. popup.description2 Technological conditions were worked out and nanocomposite materials were created based on Si matrices and embedded Bi12SiO20 and Bi12GeO20 nanocrystals. A technology for obtaining Si:BSO and Si:BGO nanocomposites was developed. The formation of a BGO (BSO) crystal structure in the pores of the matrix was confirmed by X-ray structural studies. Polarized Raman spectra of Bi12GeO20 and Bi12SiO20 crystals were obtained, systematized according to irreducible representations, and polarized Raman spectra of Bi12GeO20 and Bi12SiO20 were calculated from the first principles. Raman spectra of the Si:Bi12GeO20 nanocomposite material were measured and analyzed. The diffraction pattern at a wavelength of 130 GHz was calculated under periodic illumination of a Ge plate with optical radiation. A photonic crystal formed by submillimeter-thick silicon columns was simulated, the frequency spectrum of the crystal was determined, and a band gap of 120 GHz was detected in the frequency range from 560 to 680 GHz. A stand was created for measuring the photogeneration of carriers in the studied materials and photoconductivity measurements were carried out in the materials Si, Ge, Se, Bi12GeO20 and Bi12SiO20. The properties of Si, Ge, Bi12GeO20 (BGO), Bi12SiO20 (BSO), thin films of selenium Se and indium tin oxides (ITO) in the frequency ranges of 85-146 GHz were studied in detail, the spectral transmission and reflection functions in this region of the spectrum were measured, and the optical constants of materials in the THz region of the spectrum were determined based on the amplitude and phase spectral dependences of the S-parameters. The influence of the Ge crystal thickness and the illumination intensity on the photomodulation of radiation with a frequency of 130 GHz in reflection and transmission geometries was studied. Models of THz and millimeter-wave radiation modulators were created. The developed modulators are not inferior to foreign analogues in terms of modulation depth and Product Description popup.authors Andrushchak Nazarii A. Shchur Yaroslav Y. Adamiv Volodymyr Bendak Andrii V. Venhryn Bohdan Ya. Balaban Oksana V. Danylov Andrii B. popup.nrat_date 2025-11-28 Close