Figure 5
From: Domain wall of a ferromagnet on a three-dimensional topological insulator

Difference of the electron density distribution Δρ(x) (red curve) between the Neel and the Bloch domain wall with equal chemical potential μ.
The horizontal axis is the x coordinate. It is well explained by the formula Eq. (25) semi-quantitatively as shown by a black dotted curve. Especially, the dotted curve fits perfectly at tails, where the formula Eq. (25) is expected to be accurate.