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Information × Registration Number 0213U003806, 0112U003687 , R & D reports Title Magnetic and magneto-acoustic effects in weak ferromagnets and ferrites popup.stage_title Head Berzhansky Vladimir Naumovich, Registration Date 30-01-2013 Organization National Taurida V. Vernadsky University popup.description2 Object: noncollinear antiferromagnets of easy plane anisotropy Goal: analysis of parametrical processes in the system of traveling magneto-elastic waves in hematite and analysis of the nature of magnetic anisotropy induced by uniaxial pressure in iron borate. Synthesis of iron-borate monocrystals diamagnetically diluted with gallium. Methods of investigation: mathematical simulation, non-linear ultrasonic spectrometry, differential thermal analysis, X-ray diffraction. Results: The model of three-wave binding for traveling wave regime with different polarizations of electromagnetic pumping has been first developed for the high-temperature noncollinear easy-plane anisotropy antiferromagnets. It has been established that the lowest values of instability threshold are realized under transverse pumping. The non-linear phase shift of ultrasonic triads has been determined. The rule of modulation of the phase of pumping field in order to compensate nonlinear phase shift and in order to restore the explosive supercritical dynamics of traveling waves has been proposed. It has been proved that the explosive instability and the spatial localization of the three-wave interactions of traveling waves can be observed in strongly nonlinear medium. The theory of magnetic anisotropy which is induced by uniaxial pressure in basic plane of rhombohedral crystal has been first developed. It has been established that the accounting of induced anisotropy or the accounting of direct uniaxial pressure are equivalent for the study of magnetic and magnetoacoustic effects in iron borate. The processes of magnetization of iron borate under uniaxial pressure and under magnetic field, both of which are acting in basic plane, have been studied theoretically and experimentally. It has been shown that both the collinear magnetic phase and the angular magnetic phase are transformed into one angular phase if field and pressure are noncollinear one other. The monocrystals of iron borate which are diamagnetically diluted with gallium have been synthesized. Product Description popup.authors Євстаф'єв Олександр Іванович Ляшко Наталія Василівна Максимова Олена Михайлівна Полулях Сергій Миколайович Попов В'ячеслав Валерійович Постивей Наталія Сергіївна Скібінський Костянтин Михайлович Стругацький Марк Борисович Ягупов Сергій Володимирович popup.nrat_date 2020-04-02 Close