Work

Evolution of nodal line induced out-of-plane anomalous Hall effect in Co 3 Sn 2 S 2

Year: 2025

Type: article

Abstract: Weyl semimetals have attracted considerable research interest over the past decade, with a number of intriguing transport phenomena reported. Magnetic Weyl semimetals, which break time reversal symmetry, have been predicted and recently discovered. Co 3 Sn 2 S 2 is a magnetic Weyl semimetal that exhibit a giant anomalous Hall effect (AHE) when the magnetic moments are aligned along the c axis. In this paper, we report the evolution of the AHE with an external magnetic field applied in the a b plane and current along the c axis, namely, the out-of-plane AHE of Co 3 Sn 2 S 2 . Density functional theory calculations predict a finite out-of-plane AHE when the spins are fully aligned in the a b plane. The evolution of the magnetic structure modifies the nodal line distribution and the Berry curvature, resulting in a weaker AHE with an amplitude of 200 S c m − 1 at the saturation field. To ensure the alignment of the magnetic field in the a b plane, a two-round scanning process was performed experimentally. After this, the out-of-plane AHE was measured at multiple temperatures. The observed AHE signals with applied fields of 1 and 2 T were in good agreement with theoretical predictions. These results suggest that engineering the anomalous Hall effect may be possible by designing the symmetry relation of the local Berry curvature.

Source: Physical review. B./Physical review. B

DOI: 10.1103/physrevb.111.045157