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Archeological ceramic paste material typically consists of a mix of a clay matrix and various millimeter and sub-millimeter sized mineral inclusions. Micro X-ray fluorescence (XRF) is a standard compositional classification tool and in this work we propose and demonstrate an improved fluorescence map processing protocol where the mineral inclusions are automatically separated from the clay matrix to allow independent statistical analysis of the two parts. Application of this protocol allowed us to enhance the discrimination between different ceramic shards compared with the standard procedure of working with only the spatially averaged elemental concentrations. Using the new protocol, we performed an initial compositional classification of a set of 83 ceramic shards from the western slopes of the south central Andean region in the Arica y Parinacota region (Chile). Comparing the classifications obtained using the new versus the old (average concentrations only) protocols, we found that some samples were erroneously classified with the old protocol. From an archaeological perspective, a broad and heterogeneous regional sample set was used in this experimental study due to the fact that this was the first such analysis to be performed on ceramics from this region. This allowed a general overview to be obtained, however further work on more specific sample sets will be necessary to extract concrete archaeological conclusions. [ABSTRACT FROM AUTHOR]

In preparation for real space studies of magnetic domains in a pump-probe setup at free-electron laser sources, it is necessary to develop an imaging method compatible with the linearly polarized radiation available at these sources. We present results from a prototype experiment performed at the synchrotron source BESSY II, using a modification of existing phase retrieval techniques. Our results show that it is possible to image magnetic domains in real space using linear polarized light, and we introduce the concept of a reliability map of our reconstructions using Gabor transforms. [ABSTRACT FROM AUTHOR]

In this work, we take a step toward nanometer resolution magnetic tomography, demonstrating the use of resonant magnetic x-ray scattering for three-dimensional (3D) characterization of Co/Pd multilayers. Trading coherence for x-ray flux, we measured magnetic scattering out to full period resolutions of 20 nm for incidence angles up to 75° from normal incidence, which was sufficient for a semiquantitative analysis of the 3D magnetic domain structure of such films. For the analysis of such patterns, we developed a scattering model based upon multiple plane propagation of the beam through the sample, taking into account the effects of multiple scattering not accounted for with Born or Rytov approximation based models. Our results demonstrate that 3D statistical characterization of nanoscale magnetic features is currently possible, and it is expected that the advent of high brilliance sources such as MAX IV in Sweden and SIRIUS in Brazil will provide the coherent flux necessary to permit the generalization of this work to nanometer resolution magnetic tomography. [ABSTRACT FROM AUTHOR]

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]