Anomalous Hall effect and magnetoresistance in micro-ribbons of the magnetic Weyl semimetal candidate PrRhC2

TL;DR

This study investigates the magnetotransport properties of PrRhC2, a candidate magnetic Weyl semimetal, revealing anomalous Hall effects and angular-dependent magnetoresistance linked to its topological and magnetic characteristics.

Contribution

It reports the synthesis of PrRhC2 single crystals and detailed magnetotransport measurements, highlighting topological effects and magnetic correlations in this rare-earth carbide.

Findings

Observation of anomalous Hall effect below 6K

Fourfold angular dependence of magnetoresistivity

Presence of non-collinear antiferromagnetic state below 20K

Abstract

PrRhC2 belongs to the rare-earth carbides family whose properties are of special interest among topological semimetals due to the simultaneous breaking of both inversion and time-reversal symmetry. The concomitant absence of both symmetries grants the possibility to tune the Weyl nodes chirality and to enhance topological effects like the chiral anomaly. In this work, we report on the synthesis and compare the magnetotransport measurements of a poly- and single crystalline PrRhC2 sample. Using a remarkable and sophisticated technique, the PrRhC2 single crystal is prepared via focused ion beam cutting from the polycrystalline material. Our magnetometric and specific heat analyses reveal a non-collinear antiferromagnetic state below 20K, as well as short-range magnetic correlations and/or magnetic fluctuations well above the onset of the magnetic transition. The transport measurements on the PrRhC2 single crystal display an electrical resistivity peak at 3K and an anomalous Hall effect below 6K indicative of a net magnetization component in the ordered state. Furthermore, we study the angular variation of magnetoresistivities as a function of the angle between the in-plane magnetic field and the injected electrical current. We find that both the transverse and the longitudinal resistivities exhibit fourfold angular dependencies due to higher-order terms in the resistivity tensor, consistent with the orthorhombic crystal symmetry of PrRhC2. Our experimental results may be interpreted as features of topological Weyl semimetallic behavior in the magnetotransport properties.