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Information × Registration Number 0214U002158, 0110U004586 , R & D reports Title Femtooptics of nanoparticles of noble metals, semiconductors and fullerene-containing organic compounds. popup.stage_title Head Blonskyy Ivan Vasyl'ovych, Registration Date 22-01-2014 Organization Institute of physics NASU popup.description2 Principles of cluster formation in pulsed laser ablation of solid targets have been determined. Colloidal solutions of nanoparticles of selenide and telluride of cadmium have been prepared by ablation of corresponding crystalline targets in liquids by femto -and nanosecond lasers. Aqueous solutions of colloidal clusters of (CdSe)33,34 stabilized by cysteine have been synthesized. By the methods of optical absorption spectroscopy, photoluminescence, photoluminescence excitation, and studies of the kinetics of relaxation of photoluminescence in nano- microsecond time interval, and kinetics of induced by powerful femtosecond laser pulses bleaching in femto- picosecond range, the peculiarities of electronic excitations in semiconductor structures of binary semiconducting cadmium selenide of different dimensions and structures in nanometer size range have been studied: nanoparticles (crystalline lattice of bulk material, zero-dimensional, weak quantum confinement, wide size dispersion), nanoclusters (closed-shell atomic structure, zero-dimensional, strong quantum confinement, no size dispersion), and nanoplatelets (different from the bulk material crystal lattice, two-dimensional, no thickness dispersion, and undefined area dispersion). Temporal relaxation constants of electronic excitation processes are determined quantitatively. A new mechanism of photoluminescence (analogue of Auger process involving holes) in nanoplatelets of 6 monolayers thickness has been discovered. An unusual ("prolonged") exciton recombination kinetics of electron - heavy hole excitons has been found. A qualitative explanation (with diagrams of electronic transitions) of the observed phenomena is presented. Product Description popup.authors Блонський Іван Васильович Головченко Олена Миколаївна Дмитрук Ігор Миколайович Дмитрук Андрій Миколайович Кадан Віктор Миколайович Коренюк Петро Іванович Шинкаренко Євген Вікторович popup.nrat_date 2020-04-02 Close