Spin-orbit coupling in single layer ferrimagnets: direct observation of spin-orbit torques and chiral spin textures

TL;DR

This study reveals intrinsic spin-orbit coupling effects in a single-layer GdFeCo ferrimagnet, demonstrating measurable spin-orbit torques and chiral spin textures without heavy metal interfaces, and explores their optimization.

Contribution

It provides direct experimental evidence of spin-orbit effects and chiral textures in single-layer ferrimagnets, highlighting their dependence on composition and thickness variations.

Findings

Spin-orbit torques are present in single-layer GdFeCo.

Chiral magnetic textures are observed without heavy metal interfaces.

Effects can be optimized by adjusting layer thickness or combining with interfacial effects.

Abstract

We demonstrate that effects of spin-orbit coupling and inversion asymmetry exist in a single GdFeCo ferrimagnetic layer, even without a heavy metal interface. We use electric transport measurements to quantify the spin-orbit torques. We measure the Dzyaloshinskii-Moriya interaction using Brillouin light scattering measurement technique, and we observe the resulting chiral magnetic textures using x-ray PEEM microscopy. We attribute these effects to a composition variation along the thickness, that we observed by scanning transmission electron microscopy. We show that these effects can be optimized by varying the GdFeCo thickness or by combining them with interfacial effects.