Creation of Localized Skyrmion Bubbles in Co/Pt Bilayers using a Spin Valve Nanopillar

TL;DR

This paper demonstrates the creation and control of localized skyrmion-like magnetic domains in Co/Pt bilayers using a spin valve nanopillar, advancing the potential for room-temperature skyrmion-based devices.

Contribution

It introduces a novel device architecture enabling independent control of local magnetic domains and provides evidence of skyrmion symmetry through simulations.

Findings

Localized domains can be switched independently from the extended film.

Micromagnetic simulations suggest skyrmion symmetry of the localized domain.

First step toward room-temperature skyrmion control using spin-transfer torque.

Abstract

We fabricate devices in which a magnetic nanopillar spin valve makes contact to a Co/Pt bilayer thin film with perpendicular magnetic anisotropy, in order to achieve local control of domains in the Co/Pt bilayer underneath the nanopillar. The goal is to develop the ability to nucleate, detect, and annihilate magnetic skyrmions in the Co/Pt using spin-polarized currents from the nanopillar. We demonstrate the ability to distinguish the local behavior of the Co/Pt film beneath the nanopillar from the extended film and show that the two can switch independently of each other. This allows us to isolate a localized domain under the pillar that can be controlled separately from the rest of the Co/Pt film using applied currents and magnetic fields. Micromagnetic simulations indicate that this localized domain has skyrmion symmetry. Our results represent a first step toward controlling room-temperature skyrmions using localized spin-transfer torque.