Switching of a large anomalous Hall effect between metamagnetic phases of a non-collinear antiferromagnet

TL;DR

This paper demonstrates that Mn5Si3 antiferromagnetic crystals exhibit a large, anisotropic anomalous Hall effect that switches sign across different magnetic phases, despite minimal changes in overall magnetization.

Contribution

It reveals the field-induced switching of a large anomalous Hall effect between distinct non-collinear magnetic phases in Mn5Si3, highlighting the sensitivity of AHE to magnetic texture.

Findings

Large, anisotropic AHE observed in Mn5Si3

Multiple magnetic phase transitions with sign changes in AHE

AHE strongly influenced by magnetic structure, not magnetization

Abstract

The anomalous Hall effect (AHE), which in long-range ordered ferromagnets appears as a voltage transverse to the current and usually is proportional to the magnetization, often is believed to be of negligible size in antiferromagnets due to their low uniform magnetization. However, recent experiments and theory have demonstrated that certain antiferromagnets with a non-collinear arrangement of magnetic moments exhibit a sizeable spontaneous AHE at zero field due to a non-vanishing Berry curvature arising from the quantum mechanical phase of the electron's wave functions. Here we show that antiferromagnetic Mn5Si3 single crystals exibit a large AHE which is strongly anisotropic and shows multiple transitions with sign changes at different magnetic fields due to field-induced rearrangements of the magnetic structure despite only tiny variations of the total magnetization. The presence of multiple non-collinear magnetic phases offers the unique possiblity to explore the details of the AHE and the sensitivity of the Hall effect on the details of the magnetic texture.