Nature Nanotech. 9, 337–342 (2014)

Skyrmions are nanometre-sized spin textures of topological origin, found in several magnetic materials. They recently attracted the attention of the scientific community as potential information carriers in spintronics devices, resulting in their in-depth characterization both in real and reciprocal space. Now, Huyn Soon Park and co-workers report the first direct measurement of the three-dimensional spin configuration of a skyrmion lattice in Fe0.5Co0.5Si thin samples. Furthermore, with the combination of electron holography and an ingeniously engineered stepped sample, Soon Park and co-workers were able to identify a linear correlation between the skyrmion holographical phase shift and the sample thickness at a particular step, thus visualizing for the first time the magnetic flux of a skyrmion.