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Information × Registration Number 0219U003563, 0115U001469 , R & D reports Title The study of continuous and granular magnetic nano-films and 2D structures that are urgent for spintronics tasks. popup.stage_title Head Ryabchenko Sergiy Mykhajlovych, Registration Date 24-01-2019 Organization Institute of physics NASU popup.description2 The properties of magnetic anisotropy in epitaxial films of the Heusler (Co2Fe) x-Ge100-x alloy grown by partners (ІMag NASU and Royal Institute of Technology, Sweden) on a single-crystal MgO substrate were studied. X-ray diffraction (XRD) and transmission electron microscopy (TEM) measurements were made by co-authors from the University of Lisboa, Portugal. In the symmetric ? / 2? XRD scanning, peaks from secondary phases were not detected. The films are epitaxial and contain (001) oriented (Co2Fe)Ge || (001) oriented MgO substrate. From the TEM photographs, for different x it can be seen that the films form "island" structures on the surface of the MgO single-crystal substrate. When comparing the results of magnetostatic and ferromagnetic resonance (FMR) studies, it turned out that the angular dependences of the FMR spectra of films contain a contribution of crystallographic anisotropy with a 90? periodicity in the plane generated by the epitaxy of films on the (001) oriented MgO plane. But these films did not exhibit anisotropy of the coercive force for different directions of magnetization of the films in their plane. It is shown that the remanent magnetization, which is close to the saturation magnetization, after magnetization for any direction in the plane, remains in the direction in which the saturating magnetic field was introduced, and then deduced. That is, these films have an effect of the anisotropy in their plane that can turn to the direction of the saturating field, which was previously detected for the films of the same Heusler alloy grown on an amorphous SiO2 substrate. It is proposed that the absence in the magnetostatic properties of manifestation of 90 ° anisotropy, which is observed in FMR, is due to the fact that this anisotropy is less than that able to rotate, and therefore not noticeable in the angular dependences of the coercive field. The occurrence of the rotatable anisotropy is associated with the "island" structure of films in a plane with an average size of "islands" smaller than the exchange correlation length in the plane. The found properties of Geisleur (Co2Fe) x-Ge100-x thin films can be used in the design of injectors of spin-polarized electrons in spintronic devices using this alloy. Studies of the magnetic properties of magnetoactive elastomers (MAE) with carbonyl iron particles in the polydimethylsiloxane matrix (PDMS) showed that the anomalous magnetic properties of MAE are associated with the restructuring of the MAE structure under the influence of a magnetic field. It occurs because the magnetic forces between the particles in the MAE can be comparable or large elastic forces that occur when moving magnetic particles. The effect of blocking the ability of particles to move under the action of a magnetic field when the temperature drops below the solidization temperature of the matrix is revealed. The results of the MAE studies are important for the use of these "intelligent" materials in robotics. Product Description popup.authors Боднарук Андрій Васильович Бондар Олександр Васильович Калита Віктор Михайлович Ковальчук Денис Григорович Кулик Микола Миколаєвич Лозенко Альберт Федорович Рябченко Сергій Михайлович Терлецький Олег Валентинович Чорноморець Надія Федорівна popup.nrat_date 2020-04-02 Close