Induction Mapping of the 3D-Modulated Spin Texture of Skyrmions in Thin Helimagnets

S. Schneider, D. Wolf, M. J. Stolt, S. Jin, D. Pohl, B. Rellinghaus, M. Schmidt, B. Büchner, S. T. B. Goennenwein, K. Nielsch, and A. Lubk

Phys. Rev. Lett. 120, 217201 – Published 22 May 2018

Abstract

Envisaged applications of Skyrmions in magnetic memory and logic devices crucially depend on the stability and mobility of these topologically nontrivial magnetic textures in thin films. We present for the first time quantitative maps of the magnetic induction that provide evidence for a 3D modulation of the Skyrmionic spin texture. The projected in-plane magnetic induction maps as determined from in-line and off-axis electron holography carry the clear signature of Bloch Skyrmions. However, the magnitude of this induction is much smaller than the values expected for homogeneous Bloch Skyrmions that extend throughout the thickness of the film. This finding can only be understood if the underlying spin textures are modulated along the out-of-plane $z$ direction. The projection of (the in-plane magnetic induction of) helices is further found to exhibit thickness-dependent lateral shifts, which show that this $z$ modulation is accompanied by an (in-plane) modulation along the $x$ and $y$ directions.

Received 24 October 2017
Revised 29 March 2018

DOI:https://doi.org/10.1103/PhysRevLett.120.217201

Physics Subject Headings (PhySH)

Skyrmions

Magnetic nanoparticles

Transmission electron microscopy

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

S. Schneider^1,2, D. Wolf³, M. J. Stolt⁴, S. Jin⁴, D. Pohl^1,5, B. Rellinghaus^1,5, M. Schmidt⁶, B. Büchner³, S. T. B. Goennenwein^2,7, K. Nielsch^1,8, and A. Lubk³

¹Institute for Metallic Materials, IFW Dresden, Helmholtzstr. 20, 01069 Dresden, Germany
²Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062 Dresden, Germany
³Institute for Solid State Research, IFW Dresden, Helmholtzstr. 20, 01069 Dresden, Germany
⁴Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA
⁵Dresden Center for Nanoanalysis, Technische Universität Dresden, 01062 Dresden, Germany
⁶Department Chemical Metal Science, Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
⁷Center for Transport and Devices of Emergent Materials, Technische Universität Dresden, 01062 Dresden, Germany
⁸Institute of Materials Science, Technische Universität Dresden, Helmholtzstr. 7, 01069 Dresden, Germany