Anisotropic electrical and thermal magnetotransport in the magnetic semimetal GdPtBi

TL;DR

This study investigates the magnetotransport properties of GdPtBi, revealing that its electrical and thermal behaviors are influenced by magnetic interactions rather than solely by Weyl fermion physics.

Contribution

The paper provides a comprehensive experimental and theoretical analysis showing that magnetotransport in GdPtBi is dominated by magnetic interactions, challenging the Weyl fermion interpretation.

Findings

Magnetotransport is influenced by localized magnetic Gd-ions.

Weyl physics alone cannot explain the observed phenomena.

Fermi surface analysis supports magnetic interaction effects.

Abstract

The half-Heusler rare-earth intermetallic GdPtBi has recently gained attention due to peculiar magnetotransport phenomena that have been associated with the possible existence of Weyl fermions, thought to arise from the crossings of spin-split conduction and valence bands. On the other hand, similar magnetotransport phenomena observed in other rare-earth intermetallics have often been attributed to the interaction of itinerant carriers with localized magnetic moments stemming from the $4f$-shell of the rare-earth element. In order to address the origin of the magnetotransport phenomena in GdPtBi, we performed a comprehensive study of the magnetization, electrical and thermal magnetoresistivity on two single-crystalline GdPtBi samples. In addition, we performed an analysis of the Fermi surface via Shubnikov-de Haas oscillations in one of the samples and compared the results to \emph{ab initio} band structure calculations. Our findings indicate that the electrical and thermal magnetotransport in GdPtBi cannot be solely explained by Weyl physics and is strongly influenced by the interaction of both itinerant charge carriers and phonons with localized magnetic Gd-ions and possibly also paramagnetic impurities.