Tunable Room Temperature Magnetic Skyrmions in Ir/Fe/Co/Pt Multilayers

TL;DR

This paper demonstrates a tunable platform for room temperature magnetic skyrmions in multilayer films, enabling control over their stability, size, and density, which advances their potential use in memory devices.

Contribution

It introduces a method to tune skyrmion properties in Ir/Fe/Co/Pt multilayers by varying ferromagnetic composition, affecting stability, size, and density.

Findings

Skyrmion size and density can be tuned by factors of 2 and 10.

Skyrmion stability varies over an order of magnitude with composition.

The platform enables investigation of sub-50 nm RT skyrmions.

Abstract

Magnetic skyrmions are nanoscale topological spin structures offering great promise for next-generation information storage technologies. The recent discovery of sub-100 nm room temperature (RT) skyrmions in several multilayer films has triggered vigorous efforts to modulate their physical properties for their use in devices. Here we present a tunable RT skyrmion platform based on multilayer stacks of Ir/Fe/Co/Pt, which we study using X-ray microscopy, magnetic force microscopy and Hall transport techniques. By varying the ferromagnetic layer composition, we can tailor the magnetic interactions governing skyrmion properties, thereby tuning their thermodynamic stability parameter by an order of magnitude. The skyrmions exhibit a smooth crossover between isolated (metastable) and disordered lattice configurations across samples, while their size and density can be tuned by factors of 2 and 10 respectively. We thus establish a platform for investigating functional sub-50 nm RT skyrmions, pointing towards the development of skyrmion-based memory devices.