Fig. 2. Morin transition and generation of topological AFM textures.

a, Geometry of the STXM measurement, performed using linearly polarized X-rays ($\overrightarrow{k}$) that are normally incident onto the sample. b, Temperature evolution of the AFM STXM contrast obtained at the Fe L₃-edge whilst warming the buffered membrane (type C) across T_M, in the temperature range of 298–314 K. The OOP and IP contrasts are indicated in purple and yellow/orange, respectively. Scale bars, 2 µm. All the images were recorded at the same position. The energy-contrast scale was slightly varied across the transition to aid visualization¹⁰. c, Néel vector maps performed at 314 K (T > T_M), produced by rotating the sample azimuth shown in a. The R–G–B colours (key inset in c, top) and thin white bars represent the IP AFM orientations. The white regions represent OOP orientations, whereas the black regions highlight the IP AFM directions, substantially deviating from the R–G–B directions. The yellow circles and squares indicate AFM merons and antimerons, respectively. The width of the images is ∼1.5 μm.