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Information × Registration Number 0212U005696, 0112U008173 , R & D reports Title Studies of phonon, electron and magnetic excitations in ZnO:Co(Mn) and CdTe nanostructures for spintronics and optical sensors popup.stage_title Head Kalytchuk Sergii Mykhailovich, Registration Date 25-12-2012 Organization Institute of Semiconductor Physics of National Academy of Sciences of Ukrain popup.description2 Phonon and electron properties of low-dimensional structures based on ZnO and CdTe were investigated with submicron spatial resolution. Investigated Zn1-хСохO were found to be ferromagnetic at room temperature due to the indirect exchange interaction of isolated Co2+ ions as well as Co2+ ions in (Co-O-Co)n (n 1) cluster configurations. The main peculiarities of Zn2+ substitution by transition metal cation Cо2+ in ZnO matrix in photoluminescence and Raman spectra of Zn1-хСохO films were figure out. The vibrational band in the Raman spectra of Zn1-xCoxO films in the range of 500 - 600 cm-1 is shown to be the optical proof of the local vibration of a magnetic impurity in the cluster complexes containing Co2+ ions. Aluminum cations were shown to effectively incorporate into cation sublattice of ZnO during its doping by aluminum and nitrogen. The values of elastic strains and structural perfection of undoped and nitrogen and aluminum doped ZnO films were determined. Optical properties of core-shell CdSeTe-ZnS quantum dots deposited on the Si substrate were studied. The effect of aging on the photoluminescence of bio-conjugated and non-conjugated quantum dots due to quantum dots oxidation as a result of reducing the diameter of the core diameter was figure out. The bio-conjugation was found to stimulate the oxidation of quantum dots and causes the registered high-energy shift of photoluminescence band after heat treatment. Colloidal CdTe quantum dots were obtained using the aqueous solutions of ethylene glycol as the dispersion medium. The stabilizing effect of the ethylene glycol molecules on quantum dots due to the passivation of surface defects was shown and the optimum concentration of for obtaining stable dispersions of CdTe was determined. The photoluminescence spectrum of CdTe quantum dots synthesized was found to consist of a relatively narrow exciton line in the range of 2.1-2.4 eV, depending on the ratio of thioglycolic acid and L-cysteine. The Stokes shift in photoluminescence and optical absorption spectra of CdTe quantum dots was shown to increase monotonically from 170 to 200 meV with a decrease in their size from 3.1 to 1.8 nm due to the increase of the electron-phonon interaction. Product Description popup.authors Авраменко Катерина Андріївна Губанов Віктор Олександрович Калитчук Ігор Мирославович Коломис Олександр Федорович Курик Андрій Онуфрійович Насєка Юрій Миколайович popup.nrat_date 2020-04-02 Close