The focusing performance of a multilayer Laue lens (MLL) with 43.4 μm aperture, 4 nm finest zone width and 4.2 mm focal length at 12 keV was characterized with X-rays using ptychography method. The reconstructed probe shows a full-width-at-half-maximum (FWHM) peak size of 11.2 nm. The obtained X-ray wavefront shows excellent agreement with the dynamical calculations, exhibiting aberrations less than 0.3 wave period, which ensures the MLL capable of producing a diffraction-limited focus while offering a sufficient working distance. This achievement opens up opportunities of incorporating a variety of in-situ experiments into ultra high-resolution X-ray microscopy studies.

We report multimodal scanning hard x-ray imaging with spatial resolution approaching 10 nm and its application to contemporary studies in the field of material science. The high spatial resolution is achieved by focusing hard x-rays with two crossed multilayer Laue lenses and raster-scanning a sample with respect to the nanofocusing optics. Various techniques are used to characterize and verify the achieved focus size and imaging resolution. The multimodal imaging is realized by utilizing simultaneously absorption-, phase-, and fluorescence-contrast mechanisms. The combination of high spatial resolution and multimodal imaging enables a comprehensive study of a sample on a very fine length scale. In this work, the unique multimodal imaging capability was used to investigate a mixed ionic-electronic conducting ceramic-based membrane material employed in solid oxide fuel cells and membrane separations (compound of Ce _0.8 Gd _0.2 O _{2− x} and CoFe ₂ O ₄ ) which revealed the existence of an emergent material phase and quantified the chemical complexity at the nanoscale.

Structural and order/disorder phase transitions in bimetallic Co50Pt50 nanoparticles induced by annealing have been investigated combining in situ small and wide angle x-ray scattering methods. The support of Monte Carlo simulations within a semiempirical tight-binding potential provides a realistic description of the CoPt cluster structure in the size (1.5\char21{}3.5 nm) and temperature (300\char21{}900 K) ranges, in good correlation with the experiments. If a coalescence process of as-grown noncrystalline icosahedral clusters (2 nm) induced by annealing is detected at low temperature (700$\hskip0.3em${}K) are necessary to induce, by internal atom rearrangement, the formation of decahedral structure followed by a transition to an fcc structure. We demonstrate that the expected chemical ordering occurs only from particles of fcc structure. The investigation of the chemical order/disorder transition of 3.5 nm-sized nanoparticles reveals a bistability state around 900 K with a bimodal distribution corresponding to a coexistence of almost fully ordered nanocrystals and fully disordered ones, also supported by theoretical calculations, suggesting a first-order transition in clusters as in bulk alloys.