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

TL;DR

This paper constructs the magnetic ground state phase diagram of the ferromagnetic Kondo-lattice model across 1D, 2D, and 3D lattices, revealing phase separation regions and explaining the phases via bandwidth reduction.

Contribution

It provides a comprehensive calculation of the phase diagram for the ferromagnetic Kondo-lattice model in multiple dimensions using an explicit energy comparison approach.

Findings

Phase diagrams for 1D, 2D, and 3D lattices are explicitly calculated.

Regions of phase separation are identified.

A bandwidth reduction explanation for the phase diagram is proposed.

Abstract

The magnetic ground state phase diagram of the ferromagnetic Kondo-lattice model is constructed by calculating internal energies of all possible bipartite magnetic configurations of the simple cubic lattice explicitly. This is done in one dimension (1D), 2D and 3D for a local moment of S = 3/2. By assuming saturation in the local moment system we are able to treat all appearing higher local correlation functions within an equation of motion approach exactly. A simple explanation for the obtained phase diagram in terms of bandwidth reduction is given. Regions of phase separation are determined from the internal energy curves by an explicit Maxwell construction.