Skyrmionic device for three dimensional magnetic field sensing enabled by spin-orbit torques

TL;DR

This paper demonstrates a skyrmion-based device capable of three-dimensional magnetic field sensing using spin-orbit torques, with potential for energy-efficient spintronic applications.

Contribution

The work introduces a novel skyrmion device for 3D magnetic field sensing enabled by spin-orbit torques, including experimental stabilization and measurement techniques.

Findings

Skyrmions and stripe domains stabilized in multilayers.

Magnetic fields sensed via differential measurements canceling DC offsets.

Resistance changes linked to topological transformations detected by anomalous Hall effect.

Abstract

Magnetic skyrmions are topologically protected local magnetic solitons that are promising for storage, logic or general computing applications. In this work, we demonstrate that we can use a skyrmion device based on [W/CoFeB/MgO] 1 0 multilayers for three-dimensional magnetic field sensing enabled by spin-orbit torques (SOT). We stabilize isolated chiral skyrmions and stripe domains in the multilayers, as shown by magnetic force microscopy images and micromagnetic simulations. We perform magnetic transport measurements to show that we can sense both in-plane and out-of-plane magnetic fields by means of a differential measurement scheme in which the symmetry of the SOT leads to cancelation of the DC offset. With the magnetic parameters obtained by vibrating sample magnetometry and ferromagnetic resonance measurements, we perform finite-temperature micromagnetic simulations, where we investigate the fundamental origin of the sensing signal. We identify the topological transformation between skyrmions, stripes and type-II bubbles that leads to a change in the resistance that is read-out by the anomalous Hall effect. Our study presents a novel application for skyrmions, where a differential measurement sensing concept is applied to quantify external magnetic fields paving the way towards more energy efficient applications in skyrmionics based spintronics.