Electronic properties of EuB6 in the ferromagnetic regime: Half-metal versus semiconductor

TL;DR

This paper investigates the electronic properties of EuB6 in its ferromagnetic phase, revealing a transition from half-metallic to semiconducting behavior with temperature, supported by theoretical calculations aligned with experimental data.

Contribution

It introduces a many-body theoretical approach to model EuB6's electronic properties in the ferromagnetic regime, capturing the transition from half-metal to semiconductor.

Findings

Transition from half-metallic to semiconducting behavior with temperature

Good agreement between theoretical predictions and experimental data

Temperature-dependent changes in quasiparticle properties

Abstract

To understand the halfmetallic ferromagnet EuB6 we use the Kondo lattice model for valence and conduction band. By means of a recently developed many-body theory we calculate the electronic properties in the ferromagnetic regime up to the Curie temperature. The decreasing magnetic order induces a transition from halfmetallic to semiconducting behavior along with a band broadening. We show the temperature dependence of the quasiparticle density of states and the quasiparticle dispersion as well as the effective mass, the number of carriers and the plasma frequency which are in good agreement with the experimental data.