Spin structure and dynamics of the topological semimetal Co${}_3$Sn${}_{2-x}$In${}_x$S${}_2$

Abstract

The anomalous Hall effect (AHE), typically observed in ferromagnetic (FM) metals with broken time-reversal symmetry, depends on electronic and magnetic properties. In Co${}_3$Sn${}_{2-x}$In${}_x$S${}_2$, a giant AHE has been attributed to Berry curvature associated with the FM Weyl semimetal phase, yet recent studies report complicated magnetism. We use neutron scattering to determine the spin dynamics and structures as a function of $x$ and provide a microscopic understanding of the AHE and magnetism interplay. Spin gap and stiffness indicate a contribution from Weyl fermions consistent with the AHE. The magnetic structure evolves from $c$-axis ferromagnetism at $x$ = 0 to a canted antiferromagnetic (AFM) structure with reduced $c$-axis moment and in-plane AFM order at $x$ = 0.12 and further reduced $c$-axis FM moment at $x$ = 0.3. Since noncollinear spins can induce non-zero Berry curvature in real space acting as a fictitious magnetic field, our results revealed another AHE contribution, establishing the impact of magnetism on transport.

References in corpus (11)

• Advances in the Physics of Magnetic Skyrmions and Perspective for Technology
• Mantid - Data Analysis and Visualization Package for Neutron Scattering and $\mu SR$ Experiments
• Novel magnetic states and nematic spin chirality in the kagome lattice metal YMn${}_6$Sn${}_6$
• In-plane magnetic field induced double fan spin structure with $\text{c}$-axis component in metallic kagome antiferromagnet YMn${}_6$Sn${}_6$
• Controllable chirality-induced geometrical Hall effect in a frustrated highly-correlated metal
• Chiral properties of the zero-field spiral state and field-induced magnetic phases of the itinerant kagome metal YMn${}_6$Sn${}_6$
• Spin Excitations and Spin Wave Gap in the Ferromagnetic Weyl Semimetal Co${}_3$Sn${}_2$S${}_2$
• Unusual exchange couplings and intermediate temperature Weyl state in Co3Sn2S2
• Interplay of electronic and spin degrees in ferromagnetic SrRuO${}_3$: anomalous softening of magnon gap and stiffness
• Putative helimagnetic phase in the kagome metal Co_3Sn_2-xIn_xS_2
• The magnetic structure of the topological semimetal Co${}_3$Sn${}_2$S${}_2$

Cited by in corpus (4)

• Progress and Prospects in Two-Dimensional Magnetism of van der Waals Materials
• Magnetic memory and distinct spin populations in ferromagnetic Co3Sn2S2
• NMR study of the local magnetic order in the kagome Weyl semimetal Co${}_3$Sn${}_2$S${}_2$
• In-plane Antiferromagnetism in Ferromagnetic Kagome Semimetal Co3Sn2S2