2Vernadsky Institute of General and Inorganic Chemistry of the Ukrainian National Academy of Sciences, prospekt Akademika Palladina, 32/34,
Kiev, 03142, Ukraine
3Institute of Physics of NAS of Ukraine, avenu Nauki 46, Kiev, 03680, Ukraine
Received September 30, 2016
Abstract
The work carries out the quantitative analysis of magnetic characteristics of ensembles of magnetic nanoparticles La0.6Sm0.1Sr0.3MnO3, measured at different temperatures. On the basis of performed analysis, field and temperature dependences of magnetic moment of the ensemble have been modeled. The calculations stress the governing role of the distribution of nanoparticle parameters on clue magnetic parameters of the whole ensemble: coercive field, remnant magnetization and blocking temperature. The satisfactory correlation between the experimental and calculated dependences is shown to be possible only within the suggestion that the total magnetic signal is composed of the responses from two different regions — anisotropic strong-magnetic and isotropic weak-magnetic regions. The found correlations describe temperature influence on magnetic behavior of each region. The procedure, proposed in this paper, can be used for characterization of magnetic properties of other nanoparticle systems and can be extended for analysis and prediction of the results of magneto-dynamic measurements.
PACS: 07.05.Tp Computer modeling and simulations; PACS: 75.75.–c Magnetic properties of nanostructures; PACS: 81.07.Bc Nanocrystalline materials.
Key words: magnetic nanoparticles, substituted manganites, two-level approximation, Stoner–Wohlfarth model, magnetic losses, blocking temperature.
