DFT; conduction; skyrmion; thin film DFT; thin film
Abstract :
[en] Magnetic skyrmions are localized non-collinear spin textures with a high potential for future spintronic applications. Skyrmion phases have been discovered in a number of materials and a focus of current research is to prepare, detect and manipulate individual skyrmions for implementation in devices. The local experimental characterization of skyrmions has been performed by, for example, Lorentz microscopy or atomic-scale tunnel magnetoresistance measurements using spin-polarized scanning tunnelling microscopy. Here we report a drastic change of the differential tunnel conductance for magnetic skyrmions that arises from their non-collinearity: mixing between the spin channels locally alters the electronic structure, which makes a skyrmion electronically distinct from its ferromagnetic environment. We propose this tunnelling non-collinear magnetoresistance as a reliable all-electrical detection scheme for skyrmions with an easy implementation into device architectures.
Disciplines :
Physics
Author, co-author :
Hanneken, Christian
Otte, Fabian
Kubetzka, André
Dupé, Bertrand ; Université de Liège - ULiège > Département de physique > Physique des matériaux et nanostructures
Romming, Niklas
von Bergmann, Kirsten
Wiesendanger, Roland
Heinze, Stefan
Language :
English
Title :
Electrical detection of magnetic skyrmions by tunnelling non-collinear magnetoresistance
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