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Information × Registration Number 0214U001120, 0113U001097 , R & D reports Title Size electron effects in metallic nanostructures and nanodefects of metal popup.stage_title Head Pogosov Valentin Valterovich, Registration Date 21-01-2014 Organization Zaporizhzhia National Technical University popup.description2 Оbject of study - low-dimensional metallic systems, nanodefects in metals and open quantum dots. Purpose - to install a development elements of the theory, experimental studies and the construction of physical models of size effects in mesostructures. The structure and algorithm of the automated device for measuring the surface potential were developed. The device, that based on method of Kelvin, allows measuring superficial potential of metals and semiconductors as at normal room conditions so in vacuum chamber. А formula based on the free carriers gas model with parameters depending upon film thickness and frequency, in Drude approximation for the dielectric function is introduced to calculate infrared transmittance of metallic films of several nanometers thickness. Results of calculation are compared with experimental data for transmittance of Pb films of 0-5 nm thickness within the 1000-4000 cm-1 frequency range. It is found that an effective mass of charge carriers is noticeably less in a film than in a bulk metal. A frequency dependence of the relaxation rate and plasma frequency is discovered. ТInfluence of the dielectric environment on dimensional Fermi energy oscillations of nanometer metal films was investigated . The analytical expression for the dielectric function of the metal nano film was obtained . The influence of the geometry of the cross-section on the energy characteristics of 1D- metal systems was investigated . Size dependence of the Fermi energy of circular and elliptical nanowires was obtained . Changing the shape of the cross-section nanowires in the first order of perturbation theory can be taken into account by modifying the boundary condition for the radial wave function of electrons. The real and imaginary parts of the optical conductivity elliptical nanowires was calculated . Algorithm for calculating the S-matrix for electron motion in one-dimensional potential profiles of arbitrary shape has been developed. Poles of the S-matrix, and the broadening of the resonance energy levels of quasi-stationary cylindrical quantum dot in an external electric field were calculated. Theory of single-electron tunneling current-voltage characteristics and open metal quantum dot based on the broadening of the levels have been modified. In the framework of the density-functional-theory and direct variational method the energy formation of monovacancy, the binding energy, and the work functions of quasifree and localized positron and positronium atom has been calculated. It is shown that the vacancies into the subsurface region of the metals with negative positron work function can lead to the change in the sign of the work function. The dielectric coating of the metal surface leads to the change in the sign of the quasifree positron work function too. We compare these results with available experimental data. Product Description popup.authors Бабіч А.В. Булатецька Т.В. Вакула П.В. Жавжаров Є.Л. Качан В.О. Коротун А.В. Курбацький В.П. Погосов В.В. popup.nrat_date 2020-04-02 Close