Discovery of a magnetic Dirac system with large intrinsic non-linear Hall effect

TL;DR

This paper reports the discovery of a magnetic Dirac antiferromagnet, TaCoTe2, exhibiting a large intrinsic non-linear Hall effect that is highly tunable by the Nél vector orientation, promising for spintronic applications.

Contribution

The study provides experimental and theoretical evidence of topological Dirac fermions and a large, tunable non-linear Hall effect in TaCoTe2, a magnetic Dirac system.

Findings

Identification of spin-orbit coupling-induced gaps at the Fermi level.

Observation of a large intrinsic non-linear Hall conductivity.

High sensitivity of Hall effect to Nél vector orientation.

Abstract

Magnetic materials exhibiting topological Dirac fermions are attracting significant attention for their promising technological potential in spintronics. In these systems, the combined effect of the spin-orbit coupling and magnetic order enables the realization of novel topological phases with exotic transport properties, including the anomalous Hall effect and magneto-chiral phenomena. Herein, we report experimental signature of topological Dirac antiferromagnetism in TaCoTe2 via angle-resolved photoelectron spectroscopy (ARPES) and first-principles density functional theory (DFT) calculations. In particular, we find the existence of spin-orbit coupling-induced gaps at the Fermi level, consistent with the manifestation of a large intrinsic non-linear Hall conductivity. Remarkably, we find that the latter is extremely sensitive to the orientation of the N\'eel vector, suggesting TaCoTe2 a suitable candidate for the realization of non-volatile spintronic devices with an unprecedented level of intrinsic tunability.