Spin Fluctuations in Disordered Metallic Ferrimagnetic Alloys

Abstract:

We propose a theory for the quantitative description of the thermodynamic, magnetic and electronic properties of disordered alloys of transition metals and normal, for example, the system Fe-Al, as obtained from melting, and in the form of metastable states produced by mechanical grinding. System of itinerant d-electrons with two constants of the intra-atomic exchange interaction is investigated by the fluctuating field approach. Fundamentally new feature of the system is the presence of several ferrimagnetic solutions, transitions between which give variety to the temperature dependence of the magnetic characteristics of disordered alloys. Results of calculation of the temperature dependences of the magnetic characteristics of iron aluminum alloys are considered as an application of the theory.

• Periodical: Solid State Phenomena (Volumes 233-234)
• Pages: 25-29
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.233-234.25
• Online since: July 2015
• Authors: Vladimir I. Grebennikov*, Danil I. Radzivonchik
• Keywords: Atomic Magnetic Moments, Fe-Al Disordered Alloys, Itinerant Electron Magnetism, Magnetic Phase Transitions, Thermal Spin Fluctuations

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