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arXiv · 1008.1148

Ferromagnetic phases in spin-Fermion systems

N. Karchev
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Abstract

Spin-Fermion systems which obtain their magnetic properties from a system of localized magnetic moments being coupled to conducting electrons are considered. The dynamical degrees of freedom are spin-$s$ operators of localized spins and spin-1/2 Fermi operators of itinerant electrons. Renormalized spin-wave theory, which accounts for the magnon-magnon interaction, and its extension are developed to describe the two ferrimagnetic phases in the system: low temperature phase $0<T<T^{*}$, where all electrons contribute the ordered ferromagnetic moment, and high temperature phase $T^{*}<T<T_C$, where only localized spins form magnetic moment. The magnetization as a function of temperature is calculated. The theoretical predictions are utilize to interpret the experimentally measured magnetization-temperature curves of $UGe_2$..

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N. Karchev. 2010-08-06. Ferromagnetic phases in spin-Fermion systems. https://doi.org/10.1140/epjb%2Fe2010-00249-4

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