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Information × Registration Number 0204U006473, 0104U000062 , R & D reports Title Development technology of nanocrystal surface alloys with controlled properties popup.stage_title Head Pogoriliy, Registration Date 15-11-2004 Organization Institute of magnetism of NASU popup.description2 The films of metal and metal-dielectric granular nanostructured alloys with various compositions and conductivity types were manufactured in the wide concentration range. The method of controlled electron-beam co-evaporation of the alloys' components on the various types of substrates in the vacuum was used . The prepared granular nanostructured films are characterized by the anomalous magnetic, resistive, magnetotransport, resonance, optical and magnetooptical properties caused by nanosizing of granules. In magnetic granular films (Сo-Al2O3, Co-Ag, FeNi-Ag, Сo-Cu) containing the granules of magnetic material (Со, FeNi) of 1ё5 nm diameter dispersed in nonmagnetic matrix (Al2O3, Ag, Cu) the effect of giant magnetoresistance is observed, which reaches 30 % at magnetic field of 8 kOe for Co30Ag70. Nanocrystalline Co-Si films are characterized by the large value of the photoconvertion coefficient. The phenomena of electro- and photoluminescence are observed in the Si-Al2O3 films with Si nanocrystallites of1..3 nm size in Al2O3 dielectric matrix. Granular Ag-Al2O3 films (the size of Ag granulas is 10-20 nm) are effective absorbers of the optical irradiation. The magnetic nanocrystalline films of the TbFe, FeNi and LaSrMnO alloys with structures optimized through dosed heat treatment (ordinary heating, laser irradiation) have been manufactured by the magnetron method. The control of the nanocrystalline structure's formation in these films allows the tuning of magnetic and magnetotransport properties of these materials. The heat treatment leads to the formation of columnar nanocrystalline structure in the manganite LaSrMnO films. The latter results in considerable enhancement of the colossal magnetoresistance, typical for manganites in small magnetic fields, comparing with bulk and monocrystalline samples [3]. Decreasing the grain size leads to a great increase of the low-field magnetoresistance value that results from the enhancement of the spin-dependent electron scattering contribution in the nanocrystals boundaries. The elaborated technological methods allow to obtain the nanostructural films of various compositions with the wide specter of properties for different application purposes.56355635 Product Description popup.authors popup.nrat_date 2020-04-02 Close