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arXiv · 1702.00113

Observation of stable Neel skyrmions in Co/Pd multilayers with Lorentz transmission electron microscopy

Shawn D. Pollard·Joseph A. Garlow·Jiawei Yu·Zhen Wang·Yimei Zhu·Hyunsoo Yang
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Abstract

Neel skyrmions are of high interest due to their potential applications in a variety of spintronic devices, currently accessible in ultrathin heavy metal/ferromagnetic bilayers and multilayers with a strong Dzyaloshinskii-Moriya interaction. Here we report on the direct imaging of chiral spin structures including skyrmions in an exchange coupled Co/Pd multilayer at room temperature with Lorentz transmission electron microscopy, a high resolution technique previously suggested to exhibit no Neel skyrmion contrast. Phase retrieval methods allow us to map the internal spin structure of the skyrmion core, identifying a 25 nm central region of uniform magnetization followed by a larger region characterized by rotation from in- to out-of-plane. The formation and resolution of the internal spin structure of room temperature skyrmions without a stabilizing out-of-plane field in thick magnetic multilayers opens up a new set of tools and materials to study the physics and device applications associated with chiral ordering and skyrmions.

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Shawn D. Pollard, Joseph A. Garlow, Jiawei Yu, Zhen Wang, Yimei Zhu, Hyunsoo Yang. 2017-02-01. Observation of stable Neel skyrmions in Co/Pd multilayers with Lorentz transmission electron microscopy. https://doi.org/10.1038/ncomms14761

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