Fig. 2: Topological magneto-optical effect from SkL.

a Magnetic-field dependence of the Kerr rotation θ_K at 0.15 eV (red) and at 0.3 eV (blue) at 8.4 K, and of the bulk magnetization M (green curve) at 8 K. The dotted vertical lines represent the phase boundaries of the SkL phase. b Topological Kerr rotation θ_K^T at 0.24 T (IC-1 phase, green), at 0.49 T (SkL phase, red), and at 2.0 T (IC-2 phase, blue). The black dotted curve of θ_K^M(0.49 T) represents the conventional M-linear MOKE in the SkL phase at 0.49 T. c Magnetic-field dependence of θ_K^T(μ₀H_int) normalized by θ_K^M(0.49 T). Because the θ_K^M(0.49 T) traverses zero at 0.8 eV and 0.95 eV, θ_K^T(μ₀H_int)/θ_K^M(0.49 T) around these energies tends to diverge in the whole magnetic-field region, and therefore, are not shown here. For more details, see Supplementary Fig. 4. d Magnetic-field dependence of θ_K^T(μ₀H_int)/θ_K^M(0.49 T) for 0.15 eV (red), 0.3 eV (blue), 1.1 eV (purple), and 1.7 eV (green). In (c) and (d), the dotted horizontal lines represent the phase boundaries of the SkL phase.