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The ground state phase diagram of the diluted ferromagnetic Kondo-lattice model

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 نشر من قبل Martin Stier
 تاريخ النشر 2011
  مجال البحث فيزياء
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We investigate the existence of several (anti-)ferromagnetic phases in the diluted ferromagnetic Kondo-lattice model, i.e. ferromagnetic coupling of local moment and electron spin. To do this we use a coherent potential approximation (CPA) with a dynamical alloy analogy. For the CPA we need effective potentials, which we get first from a mean-field approximation. To improve this treatment we use in the next step a more appropriate moment conserving decoupling approach and compare both methods. The different magnetic phases are modelled by defining two magnetic sublattices. As a result we present zero-temperature phase diagrams according to the important model parameters and different dilutions.



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