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Information × Registration Number 0219U003188, 0114U006062 , R & D reports Title Electronic and magnetic properties of strongly correlated nanostructured systems popup.stage_title Head Krivoruchko Volodymyr Mykolayovych, Доктор фізико-математичних наук Registration Date 24-01-2019 Organization Donetsk Institute of Physics @ Engineering named after O.O.Galkin NAS of Ukraine popup.description2 The purpose of the work is to establish the fundamental laws of the formation of the electronic and magnetic properties of strongly correlated systems that are related to electronic instability, the feature of the band structure, the nature of elementary excitations, phase separation, percolation effects, size, proximity, and so on for the purposeful creation of new materials with unique physical characteristics and functional properties. Objects of study: manganites, VTNP, nanostructured systems, their magnetic and electrical properties. Research methods: contact spectroscopy, volt-ampere measurement, theoretical calculations, computer simulation, and others. Results: within the framework of the microscopic theory we consider the longitudinal dynamics of magnetization in two-subtractive ferromagnetics. It is shown that a strong renormalization of the oscillations of the longitudinal dynamics of magnetization occurs due to the processes of virtual creation and annihilation of transverse oscillations of magnetization - spin waves. Experimentally, on the example of MgB2, the thin structure of giant jumps of a stream caused by thermomagnetic avalanches is investigated. The fine structure of thermomagnetic avalanches may be a new opportunity to study the "capacity" of pinning centers for vortices in the microstructure of bulk samples. Meisnerite cavities have been discovered in a bulky MgB2 monocrystal with entangled magnetic flux, which are formed due to the demagnetization effect along the edge of the crystal along the boundary of the oppositely magnetized regions. Meisner's cavities are displaced to the center of the crystal with an increase in the external field, which corresponds to the existing model representations. The results of investigations of transport characteristics of three - dimensional 3D nanocomposites consisting of a superconductor and a spin - polarized ferromagnet are presented. From the experiments carried out, there are two factors that determine the properties of nanocomposites ? is the geometry of the component components and their mutual influence on each other (effects of proximity). The effects of hydrostatic pressure influence on transport and spectroscopic characteristics of a nanocomposite consisting of microparticles of the superconductor MgB2 and nanoparticles of ferromagnetic half-metal La0,7Sr0,3MnO3 or La0,7Ca0,3MnO3 are discussed. An experimental method of studying the electrical characteristics of nanopowder disperse systems based on ZrO2 is proposed. The possibility of using the technique for studying the processes of structuring in nanopowder disperse systems is shown. The results of theoretical investigations of the effects of proximity in structures of the multizone superconductor / ferromagnetic metal are presented. It is shown that the presented (effects of proximity) characteristics reflect the multizone structure of the superconductor and essentially depend on the state of the SF boundary and the value of the exchange interaction in the F layer. The possibility of controlling the electric field by the propagation of spin waves in thin magnetic film structures is demonstrated. These effects have important implications for magnognic devices, where the transmission of angular momentum and energy plays a key role. A new approach to the study of the influence of bound Andreevian states in the normal intermediate layer on charge transport through ballistic superconducting heterostructures is proposed. Product Description popup.authors Даніленко Ігор Анатолійович Житлухіна Олена Сергійовна Кононенко Вікторія Вадимовна Кошіна Олена Адольфівна Кучук Олена Ігорівна Савченко Андрій Сергійович Таренков Володимир Юрійович Чабанекнко Віктор Васильович Шило Артем Володимирович popup.nrat_date 2020-04-02 Close