Manipulation of topological textures in a magnetic domain wall

During experiment MI-1429, we imaged the magnetic texture of a teardrop-shape sample in Permalloy by Fourier-transform holography (FTH). To our surprise, the domain wall consisted of several Bloch-wall-type segments of alternating polarities. As MI-1429 was a 3D imaging experiment, we did not apply magnetic field to avoid perturbating the texture. Now we would like to do so, in order to elucidate the origin of the non-uniform domain wall polarity. Is this the equilibrium configuration, or does it arise from pinning on extrinsic defects? How does it react to weak magnetic field? Can we eventually manipulate the number of segments, in the perspective to encode information? We will this time focus on a 2D imaging procedure under applied magnetic field.