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Information × Registration Number 0226U000995, (0124U000392) , R & D reports Title Resonant interaction and amplification of magnetocaloric, magnetoelectric and magnetoacoustic effects in composite materials and piezoelectric-magnetics structures popup.stage_title Дослідження магнітоелектичних ефектів у композитах п’єзоелектрик-феромагнетик Head Lvov Victor A., Доктор фізико-математичних наук Registration Date 19-01-2026 Organization V.G. Baryakhtar Institute of Magnetism of the National Academy of Sciences of Ukraine (IMag NAS of Ukraine) popup.description1 Establishment of physical laws of resonant linear and nonlinear interaction between magnetic and elastic subsystems (magnon-phonon interaction) in composite magnetoelastic materials and heterostructures, and development of methods for enhancing magnetocaloric, magnetoelectric, nonreciprocal and nonlinear magnetoacoustic effects in them popup.description2 It has been proved that the value of the magnetically induced change of the temperature of ferromagnet, undergoing the structural phase transition, cannot be foreseen using the magnetic Maxwell relation, which is commonly used now for the theoretical analysis of MCE, because its use results in the significant overestimation of this value. The relation, which is suitable for evaluation of the magnetically induced temperature change has been derived taking into account the effect of magnetostructural phase transition on the energy of the magnetic subsystem of ferromagnet; it has been proved that this relation results in the much smaller value of the magnetically induced temperature change than the magnetic Maxwell relation. It was pointed out that the measurements of the magnetically induced change of the temperature of ferromagnets with adjustable (e.g., by means of the change of their chemical compositions) difference between the temperature of structural phase transition and Curie temperature would be carried out for the discovery of ferromagnets demonstrating strong MCE. It has been proved that the sharp increase of the proportionality coefficient between the electric field and magnetic field values, experimentally observed during the heating of the composite material (piezopolymer P(VDF-TrFE))/(Ni-Mn-Ga particles), is caused by the tetragonal-cubic structural phase transition in the particles. For the sake of enhancement of magnetoelectric materials of piezopolymer/(ferromagnetic particles) type, it was recommended to carry out the experiments with the materials, which include the particles that are the elongated/oblate ellipsoids or prisms with parallel to each other longest/shortest half-axes or edges. It has been proved that such ordering will increase a special kind of magnetostriction, which is inherent to these materials, and therefore, will enhance the magnetoelectric effect. Product Description popup.authors Anna O. Kosohor Titenko Anatolii M. Lidiia I. Ushii Yurii P. Stetskiv Olha L. Ryabokon' Roman V. Verba Volodymyr O. Golub Dariіa L. Popadiuk popup.nrat_date 2026-01-19 Close