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Information × Registration Number 0311U003406, 0106U001749 , R & D reports Title Theoretical and experimental researches of electronic and nuclear subsystems of real crystals popup.stage_title Теоретичні та експериментальні дослідження електронної і ядерної підсистем реальних кристалів Head Berzhansky Vladimir Naumovich, Registration Date 12-03-2011 Organization National Taurida V. Vernadsky University popup.description2 Object of investigation - Magnetic semiconductors with heterovalence impurities, solid states with molucular motion, amorphous microwires. Subject of investigation. NMR relaxation and phase transitions in magnetic semiconductors with heterovalence inpurities, NMR in solids with molecular motion, giant impedance in amorphous metals. Methods of investigation. Computer simulation, nuclear magnetic resonance, microwave method to measure complex reflection factor. Results and novelty. The theory of nuclear magnetic relaxation for impure magnets with quadrupole and non-quadrupole nuclei is built using both clusters approaches and fluctuations approaches. The computer methods to simulate pulse NMR responses for the fluctuating fields and the fluctuating interactions, including the changing valence, are developed. The NMR theory for solid states with internal molecular motion is built. The possibility to calculate NMR spectrum using the first moments of absorption line is shown. The pulse NMR responses on multi-pulse sequences are analyzed in such dynamic systems. The original cluster model for doped magnetic semiconductors is proposed. The threshold concentrations of the doping elements which cause phase transitions in both magnetic and electric crystal subsystems are determined. The original wave-guide method to measure the complex reflection factor and the method to calculate magnetic parameters of metals from the experimentally measured impedance of microwires are developed. The physical properties of cobalt-based microwires are investigated. It is shown that the external magnetic field of the order of the anisotropy field causes changes in giant microwave magnetic impedance of microwires up to 60%. Product Description popup.authors Євстаф'єв Іван Іванович Бержанський Володимир Наумович Лагунов Ігор Михайлович Полулях Сергій Миколайович Пономаренко Володимир Іванович Попов В'ячеслав Валерійович Рябушкiн Дмитро Сергійович popup.nrat_date 2020-04-02 Close