Fig. 3

Comparison between Δρ_yx and the signed density of topological charge at 5 K. a Right axis: Δρ_yx (solid line). Left axis: n_sk (squares), n_sk + n_w (circles), n_T (triangles), and Δρ_yx/(PR₀Φ₀) (cf. Eq. (2), inverted triangles with dotted line) using P = 0.56⁴³ and R₀ from Fig. 2b. For n_T, each worm is assigned several skyrmions |Q_W| by fit, and each isolated skyrmion is counted once. Empty symbols indicate points with a lower confidence, that result from counting worms in a dense background (Supplementary Note 7). Shaded area shows confidence bounds for n_T resulting from fit details (Supplementary Note 7). b, e Zooms on areas in Fig. 1i with skyrmions and isolated worms. c, f Results of MEFS fits wherein all skyrmions, including those assigned to worms, are treated as identical. The fit peak height ≈1.15 Hz, full width at half maximum (FWHM) ≈100 nm, and |Q_W| = 2 in (c) and |Q_W| = 4 in f. d, g Difference plots between b and c, and between e and f, showing the quality of the fit. Circles give the locations of the skyrmions in the fit. [The scale bars in b and e are 200 nm]