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Information × Registration Number 0201U004287, 0100U002378 , R & D reports Title Investigation of magnetic phase transitions and relaxation processes in frustrated 3D and quasi-2D metallic compounds. popup.stage_title Head Takzej Genadij Andrijovych, Registration Date 16-03-2001 Organization Institute for Magnetism of NASU popup.description2 On the basis of alloys with competing exchange interactions both the ralaxation phenomena (magnetic viscosity) and magnetic aging have been investigated for the fist time for strongly frustrated ferromagnets. The H-T phase diagram has been reconstracted for the first time. It was shown that according to mean field theory two phase lines (deAlmeida-Tauless and Gabay-Toulose) exist in H-T diagram. First one is connected with longetudial slow relaxation of spins. The next one is connected with transverse relaxation. The magnetic phase transitions in quasy 2D compounds CrNiTaS was investigated . It was shown that unlike the classical 3D spin glasses the arising of spin freesing processes is not a result of true phase transition "paramagnetic-spin glass". It was shown too that unlike the 3D systems with competing exchange interactions the reentrant "ferromagnetic-spin glass" is absent in these compounds. With the help of magnetic, X-ray and neutron investigations we have shown that the arising of a long-r ange ferromagnetic order is possible in a system of giant ferromagnetic particles. The mean magnetic moments of these particles is in order some thousand Borh magnetons. Magnetic phase transition "paramagnetic-spin glass" has been investigated in amorphous alloys near the critical concentration of arising of long-range ferromagnetic order. The lower critical dimension of spin glass was estimated for the first time for bulk magnetic systems. Product Description popup.authors popup.nrat_date 2020-04-02 Close