Noncollinear spin textures in ferromagnetic ultrathin films are currently the
subject of renewed interest since the discovery of the interfacial
Dzyaloshinskii-Moriya interaction (DMI). This antisymmetric exchange
interaction selects a given chirality for the spin textures and allows
stabilising configurations with nontrivial topology. Moreover, it has many
crucial consequences on the dynamical properties of these topological
structures, including chiral domain walls (DWs) and magnetic skyrmions. In the
recent years the study of noncollinear spin textures has been extended from
single ultrathin layers to magnetic multilayers with broken inversion symmetry.
This extension of the structures in the vertical dimension allows very
efficient current-induced motion and room-temperature stability for both N\'eel
DWs and skyrmions. Here we show how in such multilayered systems the interlayer
interactions can actually lead to more complex, hybrid chiral magnetisation
arrangements. The described thickness-dependent reorientation of DWs is
experimentally confirmed by studying demagnetised multilayers through circular
dichroism in x-ray resonant magnetic scattering. We also demonstrate a simple
yet reliable method for determining the magnitude of the DMI from static
domains measurements even in the presence of these hybrid chiral structures, by
taking into account the actual profile of the DWs. The advent of these novel
hybrid chiral textures has far-reaching implications on how to stabilise and
manipulate DWs as well as skymionic structures in magnetic multilayers.Comment: 22 pages, 5 figure
