Magnetic polarons and magnetoresistance in EuB6

TL;DR

This paper investigates how EuB6's semimetallic nature influences its magnetic polarons and magnetoresistance, providing insights into its temperature-dependent magnetic and electronic behaviors.

Contribution

It demonstrates that EuB6's semimetallic properties are crucial for understanding its magnetic polarons and magnetoresistance, advancing the interpretation of experimental observations.

Findings

Magnetic polarons form above the magnetic critical temperature.

EuB6's semimetallic nature explains its magnetoresistance behavior.

Electronic properties are influenced by its low carrier density.

Abstract

EuB6 is a low carrier density ferromagnet which exhibits large magnetoresistance, positive or negative depending on temperature. The formation of magnetic polarons just above the magnetic critical temperature has been suggested by spin-flip Raman scattering experiments. We find that the fact that EuB6 is a semimetal has to be taken into account to explain its electronic properties, including magnetic polarons and magnetoresistance.