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We present here an unprecedented way of quantifying the number of dislocations in microcrystals. This method relies on a combination of several state-of-the-art techniques: coherent x-ray diffraction used as a local probe, together with the controlled compression of micro-objects. We demonstrate that by using this method, dislocations in the microcrystal can be detected and their number precisely
Instabilities caused during the erosion of a surface by an ion beam can lead to the formation of self-organized patterns of nanostructures. Understanding the self-organization process requires not only the in-situ characterization of ensemble averaged properties but also probing the dynamics. This can be done with the use of coherent X-rays and analyzing the temporal correlations of the scattered
We show the capability of in-situ and ex-situ grazing-incidence small angle X-ray scattering (GISAXS) and diffraction (GID) techniques, using synchrotron radiation, to study the formation of self-organized nanodot patterns on semiconductor targets by ion beam sputtering (IBS). Particularly, surface nanopatterns of short-range hexagonal arrays of nanodots (as observed by atomic force microscopy ima
Ion beam sputtering is a widely used technique to obtain patterned surfaces. Despite the wide use of this approach on different materials to create surface nanostructures, the theoretical model to explain the time evolution of the erosion process is still debated. We show, with the help of simulations, that two-time correlation functions can serve to assess the validity of different models. These
A detailed characterization of the coherent x-ray wavefront produced by a partially illuminated Fresnel zone plate is presented. We show, by numerical and experimental approaches, how the beam size and the focal depth are strongly influenced by the illumination conditions, while the phase of the focal spot remains constant. These results confirm that the partial illumination can be used for cohere
Malignant melanoma is one of the most aggressive skin cancers with high potential of visceral dissemination. Since the information about melanoma genomics is mainly based on primary tumors and lymphatic or skin metastases, an autopsy-based visceral metastasis biobank was established. We used copy number variation arrays (N = 38 samples) to reveal organ specific alterations. Results were partly com
For advanced electronic, optoelectronic, or mechanical nanoscale devices a detailed understanding of their structural properties and in particular the strain state within their active region is of utmost importance. We demonstrate that X-ray nanodiffraction represents an excellent tool to investigate the internal structure of such devices in a nondestructive way by using a focused synchotron X-ray
Three-dimensional reciprocal-space maps of a single SiGe island around the Si(004) Bragg peak are recorded using an energy-tuning technique with a microfocused X-ray beam with compound refractive lenses as focusing optics. The map is in agreement with simulated data as well as with a map recorded by an ordinary rocking-curve scan. The energy-tuning approach circumvents both the comparatively large
We investigate the feasibility of applying coherent diffraction imaging to highly strained epitaxial nanocrystals using finite-element simulations of SiGe islands as input in standard phase retrieval algorithms. We discuss the specific problems arising from both epitaxial and highly strained systems and we propose different methods to overcome these difficulties. Finally, we describe a coherent mi
A novel approach to determine the structure of nanoscale crystals in three dimensions is proposed by the use of coherent x-ray Fourier transform holography in Bragg geometry. The full internal description is directly obtained by a single Fourier transform of the 3D intensity hologram. Together with the morphology, Bragg geometry gives access to the 3D displacement field within the crystal. This re
Objective: To personalize the prognostication of post-stroke outcome using MRI-detected cerebrovascular pathology, we sought to investigate the association between the excessive white matter hyperintensity (WMH) burden unaccounted for by the traditional stroke risk profile of individual patients and their long-term functional outcomes after a stroke. Methods: We included 890 patients who survived
In this review we cover and describe the application of grazing incidence x-ray scattering techniques to study and characterize nanopattern formation on semiconductor surfaces by ion beam erosion under various conditions. It is demonstrated that x-rays under grazing incidence are especially well suited to characterize (sub)surface structures on the nanoscale with high spatial and statistical accur
The intriguing thermophysical properties of CeB6 have been subject to investigation for more than 20 years. In particular, an exotic ground state, phase IV, emerges under doping with La. We report resonant x-ray scattering results on the order parameter symmetries in phase IV of Ce0.7La0.3B6, which condenses below TIV=1.5K. The results reveal a degree of mesoscopic 5d dipole antiferromagnetic orde
Biaxially strain is an important parameter in the complex phase diagram of the doped manganites that can lead to a different groundstate compared to bulk single crystals at the same doping level. For coherently strained La 2/3Ca1/3MnO3 thin films on SrTiO3 substrates, we report an unusual direction dependence of the electrical transport properties. For transport perpendicular to the substrate indu
Due to the complex interplay of magnetic, structural, electronic, and orbital degrees of freedom, biaxial strain is known to play an essential role in the doped manganites. For coherently strained La2/3Ca1/3MnO3 thin films grown on SrTiO3 substrates, we measured the magnetotransport properties both parallel and perpendicular to the substrate and found an anomaly of the electrical transport propert
We report on the preparation of high performance field-effect transistors (FETs) based on large areas of aligned films of a TTF derivative, namely, tetrakis-(octadecylthio)-tetrathiafulvalene (TTF-4SC18). TTF-4SC18 assembles into one-dimensional stacks in which the long alkyl chains promote intermolecular π-π overlapping due to their extremely closely packed nature. The films were prepared from so
X-ray absorption and magnetic circular dichroism spectra of as-deposited and postannealed Fe50 Pt50 /C granular multilayers were measured at both the Fe and Pt L2,3 edges. We demonstrate that the partial L 10 ordering of the FePt nanoparticles induced by thermal annealing results in an increase of the effective spin magnetic moments by 200% at the Fe site and by 65% at the Pt site, while the orbit
We present a study of the early stage of ripple formation on Ge(001) surfaces irradiated by a 1 keV Xe+ ion beam at room temperature and near-normal incidence. A combination of a grazing incidence x-ray scattering technique and atomic force microscopy allowed us to observe a variation of the symmetry of the surface nanopattern upon increase of the ion fluence. The isotropic dot pattern formed duri
