Engineering skyrmions in transition-metal multilayers for spintronics

TL;DR

This paper predicts the formation of tunable skyrmions in multilayer transition-metal structures, expanding their potential for spintronic applications by enabling control over skyrmion properties through interface engineering.

Contribution

It introduces a new multilayer design for skyrmions where exchange and Dzyaloshinskii-Moriya interactions can be independently tuned, advancing skyrmion engineering.

Findings

Skyrmions can be stabilized in multilayer structures with Fe biatomic layers.

Interface engineering allows control over skyrmion properties.

Density functional theory and spin dynamics simulations confirm skyrmion emergence.

Abstract

Magnetic skyrmions are localized, topologically protected spin-structures that have been proposed for storing or processing information due to their intriguing dynamical and transport properties. Important in terms of applications is the recent discovery of interface stabilized skyrmions as evidenced in ultra-thin transition-metal films. However, so far only skyrmions at interfaces with a single atomic layer of a magnetic material were reported, which greatly limits their potential for application in devices. Here, we predict the emergence of skyrmions in [4d/Fe_2/5d]_n multilayers, i.e. structures composed of Fe biatomic layers sandwiched between 4d- and 5d-transition-metal layers. In these composite structures, the exchange and the Dzyaloshinskii-Moriya interactions which control skyrmion formation can be tuned separately by the two interfaces. This allows engineering skyrmions as shown based on density functional theory and spin dynamics simulations.