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

TL;DR

This paper maps the zero-temperature phase diagram of the diluted ferromagnetic Kondo-lattice model, revealing various magnetic phases using CPA and decoupling methods to account for disorder and interactions.

Contribution

It introduces a combined CPA and decoupling approach to analyze magnetic phases in a diluted Kondo-lattice model, improving upon mean-field approximations.

Findings

Identification of multiple (anti-)ferromagnetic phases

Phase diagrams depend on model parameters and dilution levels

Comparison of mean-field and moment conserving approaches

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.