Vector Spin Chirality Switching in Noncollinear Antiferromagnets

TL;DR

This paper demonstrates temperature-driven switching of vector spin chirality in noncollinear antiferromagnetic Mn3CrN thin films, revealing a coupled magnetic, electronic, and quantum geometric transition with potential for spintronic applications.

Contribution

It provides the first experimental evidence of VSC switching in Mn3CrN and links it to quantum-geometric and Lifshitz transitions, advancing understanding of chirality control in antiferromagnets.

Findings

VSC switching occurs with temperature changes in Mn3CrN.

VSC reversal induces Fermi surface and Berry curvature reconstruction.

Transition is evidenced by anomalous Hall and resistivity measurements.

Abstract

Spin chirality provides a powerful route to control magnetic and topological phases in materials, enabling next-generation spintronic and quantum technologies. Coplanar noncollinear antiferromagnets with Kagome lattice spin geometries host vector spin chirality (VSC), the handedness of spin arrangement, and offer an excellent platform for chirality-driven phase control. However, the microscopic mechanisms governing VSC switching and its coupling to magnetic order, electronic structure, and quantum geometry remain elusive, with experimental evidence still lacking. Here, we present conclusive experimental evidence of temperature-driven VSC switching in an archetypal noncollinear antiferromagnetic manganese chromium nitride (Mn3CrN) epitaxial thin films. The VSC switching induces a concomitant quantum-geometric and Lifshitz transition, manifested through a pronounced peak in anomalous Hall conductivity remanence, a metal-insulator-like crossover in longitudinal resistivity, and a distinct evolution of x-ray magnetic circular dichroic signal. The reversal of VSC reconstructs the spin configuration, Fermi surface topology and Berry curvature, marking a unified magnetic-electronic-quantum geometric transition. This emergent behaviour, captured through magneto-transport and magneto-optic measurements, and supported by first-principles theory establish VSC as an active control knob for chirality-driven phase engineering and the design of multifunctional quantum devices.