Fig. 4
From: The evolution of skyrmions in Ir/Fe/Co/Pt multilayers and their topological Hall signature
Micromagnetic simulations of magnetic textures (Supplementary Note 5) for two sets of magnetic parameters corresponding to 5 and 200 K: a–c A = 11 pJ/m, D = 2 mJ/m2, Ms = 1.34 MA/m, Keff = 0.2 MJ/m3, and d–f A = 11 pJ/m, D = 2 mJ/m2, Ms = 1.16 MA/m, Keff = 0.05 MJ/m3. a, d 2D maps of the out-of-plane magnetization (nz) at 0.230 T. b, e Simulated MFM images at h = 40 nm obtained by integrating the stray field from the micromagnetic simulations and convolving with a model for the tip (Supplementary Note 5). c, f Contribution to the topological charge from each domain, calculated using Eq. (1) (Supplementary Note 5). Dashed lines highlight trains of skyrmions which appear as individual worms in the MFM scans. [The scale bars in a and d are 200 nm]
