  Chiral magnetic textures in ultrathin perpendicularly magnetised multilayer
film stacks with an interfacial Dzyaloshinskii-Moriya interaction have been the
focus of much research recently. The chirality associated with the broken
inversion symmetry at the interface between an ultrathin ferromagnetic layer
and a heavy metal with large spin-orbit coupling supports homochiral N\'eel
domain walls and hedgehog (N\'eel) skyrmions. Under spin-orbit torques these
N\'eel type magnetic structures are predicted, and have been measured, to move
at high velocities. However recent studies have indicated that some
multilayered systems may possess a more complex hybrid domain wall
configuration, due to the competition between interfacial DMI and interlayer
dipolar fields. These twisted textures are expected to have thickness dependent
N\'eel and Bloch contributions to the domain or skyrmion walls. In this work,
we use the methods of Lorentz microscopy to measure quantitatively for the
first time experimentally both; i) the contributions of the N\'eel and Bloch
contributions and ii) their spatial spin variation at high resolution. These
are compared with modelled and simulated structures which are in excellent
agreement with our experimental results. Our quantitative analysis provides
powerful direct evidence of the Bloch wall component which exists in these
hybrid walls and will be significant when exploiting such phenomena in
spintronic applications.
