Planar Topological Hall Effect from Conical Spin Spirals

TL;DR

This paper predicts that the planar topological Hall effect can originate from conical spin spirals, expanding understanding of magnetic textures that produce this effect and providing a way to distinguish different magnetic interactions.

Contribution

It introduces conical spin spirals as a new source of the planar topological Hall effect and discusses how symmetry analysis can differentiate between magnetic textures.

Findings

PTHE is two-fold symmetric for in-plane skyrmion tubes and conical spin spirals.

PTHE is four-fold symmetric for 90°-rotated domains of conical spin spirals.

Symmetry and magnetic-field response can distinguish between skyrmion tubes and conical spin spirals.

Abstract

Planar Topological Hall effect (PTHE) is known to arise from in-plane skyrmion tubes with an external magnetic field applied in the plane of the charge current. Here, we propose that the PTHE can robustly appear also from an unexpected source, the conical spin spiral, realizable in a variety of materials. We show that for both in-plane skyrmion tubes and conical spin spirals, the PTHE is two-fold symmetric with respect to the magnetic-field angle, while it is four-fold symmetric for 90$^{\circ}$-rotated domains of conical spin spirals. We predict that the symmetry and magnetic-field response of the PTHE can distinguish between the two scenarios, unambiguously probing the nature of the antisymmetric spin-exchange interaction and the resulting magnetic texture.