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Information × Registration Number 0220U101338, 0118U100342 , R & D reports Title Newest magnetic systems with strong connection between electrical, magnetic and structural properties and ways to control their functional capabilities popup.stage_title Head Gnezdilov Volodymyr P., Доктор фізико-математичних наук Registration Date 10-02-2020 Organization B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine popup.description2 In accordance with current trends in the world science, with regard to the priorities of studies of physical effects in materials that are promising for the latest technological applications, a comprehensive study of a number of compounds related to the fundamental ability to control their properties due to the connections between different subsystems or being in a fluctuating state have been performed. The general laws of formation of ground states and excitation spectra of a number of low-dimensional spin structures and their transformations under external influence were established, and new theoretical models were built to describe such systems. A number of new scientific results have been obtained: • In the firstly synthesized S = ½ spin-chain compound KCu(IO3)3, it was observed that the wide range between the magnetic (TN = 1.3 K) and the Jan-Teller (TJT = 175 K) transitions is characterized by disproportionate dimer orbital ordering and a large the level of spin fluctuations. • For the first time in Fe2O(SeO3)2, an antiferromagnet with saw-like spin chains an unusual separation of magnetic modes, including flat, non-dispersive, has been detected and studied. This property is most important for the probable future use of such compounds in magnonic devices. • For the first time the mechanisms of realization of crossover processes of change of the ground spin state of Co3+ in perovskites RCoO3 (R = La1-xPrx) have been experimentally investigated and theoretically explained. The strong dependence of the energy difference of these states on interatomic distances establishes the ability to control the spin crossover, and with it the magnetic, transport and structural properties of RCoO3 compounds. • A number of theoretical models concerning the mechanisms of formation of ground states and excitation spectra of magnets with different dimension and exchange topology have been developed. Obtained results are important in terms of theoretical and practical aspects . Product Description popup.authors popup.nrat_date 2020-04-02 Close