Size and density control of skyrmions with picometer CoFeB thickness variations—observation of zero-field skyrmions and skyrmion merging

The controlled formation and adjustment of size and density of magnetic skyrmions in Ta/CoFeB/MgO trilayers with low Dzyaloshinskii–Moriya interaction is demonstrated. Close to the out-of-plane to in-plane magnetic spin reorientation transition, we find that small energy contributions enable skyrmion formation in a narrow window of 20 pm in CoFeB thickness. Zero-field stable skyrmions are established with proper magnetic field initialization within a 10 pm CoFeB thickness range. Using magneto-optical imaging with quantitative image processing, variations in skyrmion distribution and diameter are analyzed quantitatively, the latter for sizes well below the optical resolution limit. We demonstrate the controlled merging of individual skyrmions. The overall demonstrated degree of comprehension of skyrmion control aids to the development of envisioned skyrmion based magnetic memory devices.

Metadaten
Author:	Christian Denker, Sören Nielsen, Enno Lage, Malte Römer-Stumm, Hauke Heyen, Yannik Junk, Jakob Walowski, Konrad Waldorf, Markus Münzenberg, Jeffrey McCord
URN:	urn:nbn:de:gbv:9-opus-109643
DOI:	https://doi.org/10.1088/1361-6463/acf6cd
ISSN:	1361-6463
Parent Title (English):	Journal of Physics D: Applied Physics
Publisher:	IOP Publishing
Place of publication:	Bristol
Document Type:	Article
Language:	English
Date of Publication (online):	2023/09/15
Date of first Publication:	2023/12/07
Release Date:	2024/04/10
Tag:	CoFeB; Kerr microscopy; skyrmions
Volume:	56
Issue:	49
Article Number:	495302
Page Number:	11
Faculties:	Mathematisch-Naturwissenschaftliche Fakultät / Institut für Physik
Collections:	weitere DFG-förderfähige Artikel
Licence (German):	Creative Commons - Namensnennung 4.0 International

Open Access