Magnons in the ferromagnetic Kondo - lattice model
نویسندگان
چکیده
The magnetic properties of the ferromagnetic Kondo-lattice model (FKLM) are investigated. Starting from an analysis of the magnon spectrum in the spin-wave regime, we examine the ferromagnetic stability as a function of the occupation of the conduction band n and the strength J of the coupling between the localised moments and the conduction electrons. From the properties of the spin-wave stiffness D the ferromagnetic phase at zero temperature is derived. Using an approximate formula the critical temperature Tc is calculated as a function of J and n.
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