Reduced models for domain walls in soft ferromagnetic films
- Lukas Döring (MPI MiS, Leipzig)
We study transition layers between two domains of constant magnetization vectors -- "domain walls" -- in soft ferromagnetic films at the cross-over from symmetric to asymmetric wall types.
In the first part of the talk, we present a reduced model for a single domain wall in an infinitely extended film that captures the optimal splitting of the wall into an asymmetric, stray-field free core and logarithmically decaying, symmetric wall tails (obtained via Gamma convergence, joint work with R. Ignat and F. Otto).
In the second part, we consider periodic domain patterns for which the wall width is not only confined by material anisotropy but also neighboring wall tails. Using methods similar to the single-wall case, we derive a reduced model that describes the influence of the tail interaction on the splitting into core and tails. Moreover, it yields a prediction for the increased rotation of the magnetization towards magnetic fields applied along the wall normal direction.