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Information × Registration Number 0217U007474, 0117U002360 , R & D reports Title Spectral and transport properties of the metal oxide compounds with elements of the transition groups popup.stage_title Head Zubov Eduard E., Registration Date 15-01-2018 Organization Donetsk State University popup.description2 The influence of silver ions and non-stoichiometry of manganese on magnetic and thermodynamic properties of lanthanum-manganese oxides has been studied. A correlation between the silver concentration and changes in magnetization, colossal magnetoresistance and magnetic entropy of such samples has been found experimentally and explained theoretically. In the framework of the mean-field theory, the nature of the spin-reorientation transition, the compensation point, the magnetic bias, and thermally induced spin inversion in the erbium orthoferrite has been established. The most general case of two-sublattice antiferromagnets with the exchange anisotropy and the exchange interaction of a metallic ion with a rare-earth ion was theoretically considered. It was theoretically shown that the characteristic energy parameters determined for free rare-earth ions can also be used in calculations of their spectra in a crystalline environment. Sets of corresponding parameters (with relativistic corrections) for the base term of all free rare-earth ions were found. The results obtained made it possible to calculate the luminescence spectra of europium-chlorine compounds which agree well with the experimental data. The frequency dependence of two-valued current-voltage curves for the contact of a metal with a complex transition-metal oxide film has been investigated. It was shown that as the frequency of the alternating current passed through the contact increases, the ratio of its maximal resistance to the minimal one decreases. Within the framework of the scattering-matrix formalism, a generalization of the linear Kubo theory for the electron transport in a metal heterostructure with an oxide tunnel barrier was obtained. A general expression for the average current was derives that significantly simplifies calculations of nonlinear contributions to the conductivity of various hybrid structures. The obtained data made it possible to propose a basically new approach to the fabrication of an internally shunted Josephson junction with a disordered oxide layer. Product Description popup.authors Білоголовський М.О. Барибін О.І. Горностаєва О.В. Житлухіна О.С. Зубов Е.Є. popup.nrat_date 2020-04-02 Close