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

M. Stier; S. Henning; W. Nolting

doi:10.1088/0953-8984/23/27/276006

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arXiv · 1106.0181

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

M. Stier·S. Henning·W. Nolting

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Abstract

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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M. Stier, S. Henning, W. Nolting. 2011-06-01. The ground state phase diagram of the diluted ferromagnetic Kondo-lattice model. https://doi.org/10.1088/0953-8984%2F23%2F27%2F276006

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