Tunable chiral spin texture in magnetic domain-walls

TL;DR

This paper demonstrates how tuning layer asymmetry in symmetric Pt/Co/Pt structures can control chiral domain wall textures and their efficiency in current-driven motion, with implications for spintronic device design.

Contribution

It introduces a method to tune the chiral field in symmetric multilayers by adjusting capping layer thickness, linking DW resistance to internal DW orientation.

Findings

Layer asymmetry tuning affects chiral field strength.

DW resistance correlates with internal DW orientation.

Precise control of chiral field enhances DW motion efficiency.

Abstract

Magnetic domain-walls (DWs) with a preferred chirality exhibit very efficient current-driven motion. Since structural inversion asymmetry (SIA) is required for their stability, the observation of chiral domain walls in highly symmetric Pt/Co/Pt is intriguing. Here, we tune the layer asymmetry in this system and observe, by current-assisted DW depinning experiments, a small chiral field which sensitively changes. Moreover, we convincingly link the observed efficiency of DW motion to the DW texture, using DW resistance as a direct probe for the internal orientation of the DW under the influence of in-plane fields. The very delicate effect of capping layer thickness on the chiral field allows for its accurate control, which is important in designing novel materials for optimal spin-orbit-torque-driven DW motion.