Magnetostatic Twists in Room-Temperature Skyrmions

July 23, 2018

Fig. 2: Reconstruction of the magnetic stray field components.*

Magnetic skyrmions are two-dimensional non-collinear spin textures characterized by an integer topological number. Room-temperature skyrmions were recently found in magnetic multilayer stacks, where their stability was largely attributed to the interfacial Dzyaloshinskii–Moriya interaction. The strength of this interaction and its role in stabilizing the skyrmions is not yet well understood, and imaging of the full spin structure is needed to address this question.

In a recent article in Nature Communications, a group of scientists from Harvard Physics, SEAS, and MIT, led by Prof. Amir Yacoby, described using a nitrogen-vacancy centre in diamond to measure a map of magnetic fields produced by a skyrmion in a magnetic multilayer under ambient conditions. The authors computed the manifold of candidate spin structures and selected the physically meaningful solution. Contrary to preceding reports, they found a Néel-type skyrmion whose chirality is not left-handed.

The authors proposed skyrmion tube-like structures whose chirality rotates through the film thickness and demonstrated that NV magnetometry, combined with our analysis method, provides a unique tool to investigate this previously inaccessible phenomenon.

Y. Dovzhenko, F. Casola, S. Schlotter, T. X. Zhou, F. Büttner, R. L. Walsworth, G. S. D. Beach & A. Yacoby, "Magnetostatic twists in room-temperature skyrmions explored by nitrogen-vacancy center spin textu re reconstruction," Nature Communications 9 (2018) doi: 10.1038/s41467-018-05158-9.