Planar Hall effect in the Weyl semimetal GdPtBi

TL;DR

This paper demonstrates the use of the planar Hall effect as a novel and effective tool to characterize chiral anomaly in the Weyl semimetal GdPtBi, highlighting its advantages over traditional methods like negative magnetoresistance.

Contribution

It introduces the planar Hall effect as a new technique for studying chiral anomaly in Weyl semimetals, specifically applied to GdPtBi, and shows its effectiveness in this material.

Findings

Large planar Hall resistivity observed at low temperature and high magnetic field.

The amplitude is mainly due to Berry curvature and chiral anomaly.

GdPtBi exhibits small orbital magnetoresistance, making it ideal for planar Hall effect studies.

Abstract

Observation of Weyl and Dirac Fermions in condensed matter systems is one of the most important discoveries. Among the very few available tools to characterize Weyl semimetals through electrical transport, negative magnetoresistance is most commonly used. Considering shortcomings of this method, new tools to characterize chiral anomaly in Weyl semimetals are desirable. We employ planar Hall effect as an effective technique in half Heusler Weyl semimetal GdPtBi to study chiral anomaly. This compound exhibits a large value of 1.5 mohm cm planar Hall resistivity at 2 K and in 9 T. Our analysis reveals that the observed amplitude is dominated by Berry curvature and chiral anomaly contributions. Through the angle dependent transport studies we establish that GdPtBi with relatively small orbital magnetoresistance is an ideal candidate to observe large planar Hall effect .