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Information × Registration Number 0219U003615, 0117U004870 , R & D reports Title Nonlinear optikal properties, spectroscopy of photosensitive, radioluminescent and complex dielectric thin film systems, optoelectronic and structural studies. popup.stage_title Head Galunov Mykola, Registration Date 07-02-2019 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 AgPbBr3, AgPb2Br5 and AgPb3Br7, films of CsPb(Cl1-xIx)3 solid solutions (0 ? x ? 1), polycrystals. The purpose of the project - to research nonlinear optical effects in photosensitive films, exciton spectra of thin films of AgPbBr3, AgPb2Br5, AgPb3Br7 and CsPb(Cl1-xIx)3 (0 ? x ? 1); to develop optoelectronic means of simultaneous research of appearance and development of both rotary and translational plastic deformation modes in polycrystalline samples in situ. 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. An experiment was conducted to record a video of small-angle scattering pattern from diffraction structures created by exposing films to radiation of normally incident, linearly polarized laser beam of milliwatt power. A computer modeling of diffraction patterns has been conducted for the first time. Conclusions on the domain structure of induced gratings and their vector characteristics were made on the basis of the model parameter values obtained. Thin films of AgPbBr3, AgPb2Br5 and AgPb3Br7 compounds and of CsPb(Cl1-xIx)3 solid solutions (0 ? x ? 1) were synthesized. Absorption spectra of the films were researched within 2-6 eV spectral range at temperatures 90-500 K. The exciton spectrum of the compounds is interpreted on the basis of electron transitions in Pb2+ ions. An optoelectronic technique was developed for simultaneous use of, firstly, colour orientation charts to determine appearance and development of a rotary plastic deformation mode, and secondly, a laser technique for tracking appearance and development of dislocation sliding which provides development of a translation mode of plastic deformation. The optoelectronic technique developed allows determination of each mode's role and contribution to plastic deformation of the whole sample, and ensures description of the mechanism of plastic deformation in the sample. The results of the project are being used for further development of nonlinear optics of thin films and exciton theory for multicomponent compounds. Product Description popup.authors Є.Бадіян Є.Маковецький А.Тонкопряд М. Галунов О. Юнакова Р. Шурінов popup.nrat_date 2020-04-02 Close