Oxygen-enabled control of Dzyaloshinskii-Moriya Interaction in ultra-thin magnetic films

TL;DR

This paper demonstrates that the magnitude and sign of Dzyaloshinskii-Moriya interaction in ultra-thin magnetic films can be controlled by oxygen coverage, enabling tailored chiral magnetic textures for advanced spintronic applications.

Contribution

The study reveals a novel method to electrically control DMI in magnetic films through oxygen coverage, expanding possibilities for designing chiral magnetic states.

Findings

DMI magnitude and sign are tunable via oxygen coverage.

Relativistic first-principles calculations support the control mechanism.

Potential extension to other electronegative ions for magnetic phase tuning.

Abstract

The search for chiral magnetic textures in systems lacking spatial inversion symmetry has attracted a massive amount of interest in the recent years with the real space observation of novel exotic magnetic phases such as skyrmions lattices, but also domain walls and spin spirals with a defined chirality. The electrical control of these textures offers thrilling perspectives in terms of fast and robust ultrahigh density data manipulation. A powerful ingredient commonly used to stabilize chiral magnetic states is the so-called Dzyaloshinskii-Moriya interaction (DMI) arising from spin-orbit coupling in inversion asymmetric magnets. Such a large antisymmetric exchange has been obtained at interfaces between heavy metals and transition metal ferromagnets, resulting in spin spirals and nanoskyrmion lattices. Here, using relativistic first-principles calculations, we demonstrate that the magnitude and sign of DMI can be entirely controlled by tuning the oxygen coverage of the magnetic film, therefore enabling the smart design of chiral magnetism in ultra-thin films. We anticipate that these results extend to other electronegative ions and suggest the possibility of electrical tuning of exotic magnetic phases.