In material science it is possible two have two regions in the same material with different (often opposite) facing magnetic polarisation. As an electron, molecule or looping electric current (all of which have magnetic moments) move from one area of polarisation to the other they most switch direction and the area in which they switch is magnetic domain wall. There are two main domain walls called the Bloch wall and Néel wall named after their respective physicists. The major difference is that in a Néel wall the moment rotates in the plane of the wall and in the Bloch wall it rotates out of the plane at a right angle.
Now it has been observed that this thin area of the domain wall has unique electric and chemical effects that can be drastically different to that of the rest of the material. Research is now being done into domain walls specifically in ferric oxides as these are very common in the electronic industry. So far it a good start has been made in analysing the crystal structure in the wall and also it has been found that for all ferric oxides tested a Néel wall was present matching theoretical predictions. This research is still emergent and a lot of work will need to be done to both understand the strange effects occurring in the domain wall and find a practical use for them.