Combing the helical phase of chiral magnets with electric currents

TL;DR

This paper investigates how electric currents can control the orientation and dynamics of helical magnetic phases in chiral magnets, revealing potential for spintronics applications through experimental and theoretical analysis.

Contribution

It introduces a theoretical framework and experimental validation for current-induced switching of helical magnetic orientations in chiral magnets.

Findings

Current pulses can switch helical orientations on demand.

Spin-transfer torques influence helical phase dynamics.

Edge and bulk defects affect helical orientation processes.

Abstract

The competition between the ferromagnetic exchange interaction and anti-symmetric Dzyaloshinskii-Moriya interaction can stabilize a helical phase or support the formation of skyrmions. In thin films of chiral magnets, the current density can be large enough to unpin the helical phase and reveal its nontrivial dynamics. We theoretically study the dynamics of the helical phase under spin-transfer torques that reveal distinct orientation processes, driven by topological defects in the bulk or induced by edges, limited by instabilities at higher currents. Our experiments confirm the possibility of on-demand switching the helical orientation by current pulses. This helical orientation might serve as a novel order parameter in future spintronics applications.