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Information × Registration Number 0219U005137, 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 20-05-2019 Organization Institute of physics NASU popup.description2 Monolayer ensembles of branched (star-shape) gold nanoparticles are produced by method of template synthesis directly on the substrate surface. This method allows distributing nanoparticles evenly over the substrate surface without significant aggregation. The average size of nanoparticles is D = (80 ± 20) nm, the average number of branches on the nanoparticle (9 ± 2), and their length - (25 ± 5) nm, in the optical absorption spectra of films there are two maxima. A peak at 620 nm for ensembles of thickness of 100 nm can be linked to the excitation of the plasmon in the core of nanoparticles, and its position depends on the size of the core. The maximum in the region of 1000 nm refers to electron vibrations on the branches of nanoparticles and its position is determined by their geometric form. The investigations of absorption spectra and optical cubic nonlinearity of thin films of palladium oxide (PdO) of different thicknesses (from 60 to 120 nm) and oxidation degree were carried out. The absorption spectra determined the width of the band gap (Eg = 2.3 eV) of polycrystalline thin films of PdO grown by oxidation of a thin layer of palladium. In the absorption spectra, a peak was found in the 480 nm region, which significantly increases and significantly narrows when the temperature drops to T = 77K. This behavior means at the possible excitonic character of the peak. The z-scan method determined the magnitude of the coefficients of the nonlinear optical receptivity of the third order ?(3) under the action of nano- and femtosecond laser radiation at wavelengths of 532 nm and 800 nm, respectively. The great value of the real part of the nonlinear susceptibility Re? (3) = -1.6 ? 10-4 esu is obtained for excitation by nanosecond pulses at a wavelength ? = 532 nm, and a fairly high value Re?(3) = 1,6 ? 10-6 esu for excitation by femtosecond pulses at wavelength ? = 800 nm. Possible mechanisms of such 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