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In multilayers of magnetic thin films with perpendicular anisotropy, domain walls can take on hybrid configurations in the vertical direction which minimize the domain wall energy, with Néel walls in the top or bottom layers and Bloch walls in some central layers. These types of textures are theoretically predicted, but their observation has remained challenging until recently, with only a few techniques capable of realizing a three dimensional characterization of their magnetization distribution. Here we perform a field dependent X-ray resonant magnetic scattering measurements on magnetic multilayers exploiting circular dichroism contrast to investigate such structures. Using a combination of micromagnetic and X-ray resonant magnetic scattering simulations along with our experimental results, we characterize the three-dimensional magnetic texture of domain walls, notably the thickness resolved characterization of the size and position of the Bloch part in hybrid walls. We also take a step in advancing the resonant scattering methodology by using measurements performed off the multilayer Bragg angle in order to calibrate the effective absorption of the X-rays, and permitting a quantitative evaluation of the out of plane (z) structure of our samples. Beyond hybrid domain walls, this approach can be used to characterize other periodic chiral structures such as skyrmions, antiskyrmions or even magnetic bobbers or hopfions, in both static and dynamic experiments. [ABSTRACT FROM AUTHOR]

Magnetic multilayers with heavy metal/ferromagnetic interfaces play an important role in data storage and spintronics due to magnetic phenomena such as perpendicular magnetic anisotropy (PMA) and magnetic skyrmion stabilization. Properties such as saturation magnetization (M s), PMA, and interfacial Dzyaloshinskii–Moriya interaction (iDMI) can be tuned by stacking engineering to tailor the multilayer magnetic ground state. Here, it is demonstrated that isolated skyrmion bubbles can be stabilized at zero magnetic field in nominally symmetric Pt/Co/Pt multilayers grown by magnetron sputtering. Interface disorder and asymmetry are strongly enhanced as the Co layer is thinned, leading to nonzero iDMI and Pt proximity induced moment (PIM) that affects both the multilayer M s and PMA. The interplay between PIM and the iDMI is behind the nucleation of skyrmion bubbles, highlighting the importance of controlling the interface phenomena to develop devices for future applications. These results also manifest the importance of considering the PIM to determine the correct magnetic parameters of ultrathin films on the zero-field spin textures stability. • Interface disorder and asymmetry are enhanced in ultrathin Co/Pt multilayers. • Enhanced Pt proximity induced moment emerges from interface disorder. • Magnetic skyrmions are stabilized at zero magnetic field and room temperature. • Dzyaloshinskii–Moriya interaction and proximity effect are behind skyrmion nucleation. [ABSTRACT FROM AUTHOR]