Fig. 1: Fresnel TEM images of SkX and identification of configurational states.

a Entire region of observed skyrmion lattice, showing the domain boundary with an average misorientation angle of 14° (black dashed line) and principle lattice vectors (arrows). The three coloured (blue, red and green) dashed lines demonstrate how the domain boundary shifts during transitions between the P_x states and the associated lateral skyrmion motion. Scale bar, 200 nm. b–g Examples of the six configurational states observed, with the time of each frame given in the bottom left corner of each image. The black arrowheads point along the row of skyrmions, in which lateral motion was taking place (same position in each image). Skyrmions with seven- and fivefold coordination (SkCoH and SkCoP, respectively) are highlighted by the conjoined pentagons and heptagons. Scale bar, 200 nm. h A portion of the transition data showing the progression of reversible transitions between states shown in b–g. The markers (b–g) additionally indicate the time of occurrence of the images shown in b–g. Colour in each panel is associated with the identified configurational states, according to the bottom key.