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Information × Registration Number 0218U001427, 0117U004870 , R & D reports Title Nonlinear optical properties, spectroscopy of photosensitive, radioluminescent and complex dielectric thin film systems, optoelectronic and structural studies. popup.stage_title Head Galunov Nikolai Zakharovych, Registration Date 13-03-2018 Organization Kharkov National University named after V.N. Karazin popup.description2 The object of research - thin films with real-time photosensitivity; films of the triple compounds of KPb2Br5 and CuPb3Br7, polycrystals. The purpose of the project - to research nonlinear optical effects in photosensitive films, exciton spectra of thin films of KPb2Br5, KPb2(Cl1-хBrx)5 0<х<1, and CuPb3Br7; to develop a laser technique for determination of content of impurities and their distribution at the surface of crystalline materials.Methods of the research - vacuum preparation of films; irradiation of the films by monochromatic light; spectroscopic, diffractional and microscopic researches of morphology and structure; laser and diffractional methods of research. A bistability has been found experimentally for the first time in the dependence of waveguide mode intensity in AgCl-Ag film on the intensity of the laser beam which creates periodic gratings in the film with double diffraction reflexes from it. The grating parameters calculated with the theoretical model are in accordance with measured ones. Thin films of the following compounds were synthesized: KPb2Br5, KPb2(Cl1-хBrx)5 0 х 1, and superionic conductor CuPb3Br7. Absorption spectra of the compounds have been researched in spectral band of 2-6 eV at temperatures 90-500 K. Exciton spectra of the compounds are examined on the basis of electron transitions in Pb2+ ion. A laser technique has been developed for detection of impurities at surfaces of polycrystalline samples. It was demonstrated experimentally that laser beam interaction with polished surface of a crystalline material results in detection of local melted regions enriched with impurities. They can be detected at certain lighting conditions. When using the developed technique, one can determine not only impurities distribution at the sample surface but their content as well. It has been confirmed by experimental researches which allowed us to detect content and surface distribution of iron impurities at the aluminum sample surface. The results of the project are being used for further development of nonlinear optics of thin films and exciton theory for multicomponent compounds. A forecast on development of the object of research - further extended research of the nature and mechanisms of unusual optical phenomena in various thin films; use of the techniques developed would allow one to determine content of impurities and their distribution in polycrystalline materials. Product Description popup.authors Є.Бадіян Є.Маковецький А. Дергачова А.Тонкопряд М. Галунов О. Юнакова Р. Шурінов С. Вовк popup.nrat_date 2020-04-02 Close