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Information × Registration Number 0218U002568, 0115U003676 , R & D reports Title The study of quantum - dimensional and nonlinear - optical properties of complex nanoparticles and arrays such as "quantum solid" based on A2B6 semiconductors and noble metals as the material media nanophysics and nanoelectronics. popup.stage_title Head Brodyn M.S., Registration Date 13-04-2018 Organization Institute of physics NASU popup.description2 In the third stage of the project, new quantum structures based on zinc selenide were investigated. They were synthesized and stabilized in colloidal solutions using various stabilizers (thioglycerol and thioglycolic acid) and deposited on silicon dioxide onto spherical surfaces. The obtained results indicate a significant (electrostatic) effect of the stabilizer molecules on the energy of charge carriers in quantum dots. With the spatial effect of excitons, it also enables to change the energy of charge carriers in quantum dots by reducing or increasing the potential barrier at the interface of two phases. Synthesis of films based on silicon dioxide spheres covered with ZnSe quantum dots on transparent substrates also allowed to investigate the effect of the polarization effect caused by the jump of the dielectric constant at the boundary of the quantum dot-matrix section with the energy of charge carriers. At first, two contributions of the energy of the excitons (polarization and spatial) was experimentally divided. In general, the results obtained at the third stage of the project can be used in different areas of nanophysics, in particular, in photovoltaic structures (solar cells of the 3rd generation). Results of the studies of the 3rd order nonlinear optical properties of polycrystalline thin PdO films, grown by oxidation of a thin layer of palladium, were achieved. In the absorption spectra of films, a peak in the 480 nm region was found. It significantly increases and substantially narrowed with a decrease of temperature to 77 K. That indicates its possible exciton nature. Using the methods of the degenerate four-wave mixing and Z-scan, under the action of pulsed laser radiation with a wavelength of 532 nm and a pulse duration of 9 nsec, a real part of the nonlinear susceptibility of the third order Re?(3) = -1,6?10-4 esu. The possible mechanisms of such a high cubic optical nonlinearity were proposed. Product Description popup.authors Безкровний Олексій Сергійович Бондар Микола Володимирович Бродин Михайло Семенович Ляховецький Володимир Романович Матвєєвська Неоніла Анатолієвна Матейченко Павло Вікторович Руденко Валентин Іванович Стьопкін Віктор Іванович popup.nrat_date 2020-04-02 Close