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We present a combination of µLaue X‐ray diffraction and X‐ray excited optical luminescence (XEOL) techniques to map local strain, orientation, and light emission in metalorganic vapor phase epitaxy (MOVPE) core–shell InGaN/GaN multiple quantum wells (MQW) wires dispersed on silicon substrates. The components of the deviatoric strain tensor averaged along the beam footprint were quantified with a measurement precision better than 9 × 10−5 and an accuracy of approximately 4 × 10−4. This measurement quality is achieved by carefully calibrating the analysis chain with a Ge crystal and verifying it with measurements of the unstrained Si substrate reference. The µLaue mapping of the components of the deviatoric strain confirms the high crystal quality and the impact of the MQW shell grown only in the upper part of the GaN core, as evidenced by the local variations of the full width at half maximum of the diffraction peaks and of the lattice rotation tensor. The two deviatoric tensors of the GaN core and InGaN/GaN shell can be measured independently and are in quantitative agreement with 3D finite element method (FEM) simulations. The structural information is correlated with XEOL measurements, whose spectral analysis reveals the main contributions to light emission: the major UV‐blue MQW emission from the m‐plane at the top of the wires, with a gradient varying from 406 nm at the top of the MQW to 397 nm at the bottom, with a secondary emission of a semipolar r‐plane facet at ∼470 nm; the near‐band‐edge GaN signal at ∼363 nm; and the usual yellow defect‐band luminescence, centered at 560 nm. The paper also highlights the potential of these techniques to obtain statistics on semiconductor heterostructures and their automation capabilities for measurements and analysis. Micro‐Laue diffraction and excited optical X‐ray luminescence are used to study InGaN/GaN core‐shell wires on the BM32 beamline at the European Synchrotron. Multimodal imaging of X‐ray fluorescence, deviatoric strain tensors and optical emissions is performed using simultaneous mapping. Finite element calculations confirm the deviatoric strain tensors of the core and shell, as determined by experimentation.

The simultaneous measurement of two Bragg reflections by Bragg coherent X-ray diffraction is demonstrated on a twinned Au crystal, which was prepared by the solid-state dewetting of a 30 nm thin gold film on a sapphire substrate. The crystal was oriented on a goniometer so that two lattice planes fulfill the Bragg condition at the same time. The Au 111 and Au 200 Bragg peaks were measured simultaneously by scanning the energy of the incident X-ray beam and recording the diffraction patterns with two two-dimensional detectors. While the former Bragg reflection is not sensitive to the twin boundary, which is oriented parallel to the crystal–substrate interface, the latter reflection is only sensitive to one part of the crystal. The volume ratio between the two parts of the twinned crystal is about 1:9, which is also confirmed by Laue microdiffraction of the same crystal. The parallel measurement of multiple Bragg reflections is essential for future in situ and operando studies, which are so far limited to either a single Bragg reflection or several in series, to facilitate the precise monitoring of both the strain field and defects during the application of external stimuli.

For the characterization of the mechanical properties of materials the precise measurements of stress‐strain curves is indispensable. In situ nano‐mechanical testing setups, however, may lack the precision either in terms of strain or stress determination. Recently, the custom‐built scanning force microscope SFINX was developed which is compatible with third‐generation synchrotron end‐stations allowing for in situ nano‐mechanical tests in combination with nanofocused synchrotron x‐ray diffraction that is highly sensitive to strain and defects. The usage of a self‐actuating and self‐sensing cantilever tremendously increases the compactness of the system but lacks deflection sensitivity and, thus the force measurement. This deficiency is resolved by in situ monitoring the diffraction peaks of the Si cantilever by Laue microdiffraction during the nano‐indentation of a gold crystal. The orientation and, hence, the deflection of the Si cantilever is deduced from the displacement of the Si Laue spots on the detector giving force accuracies of better than 90 nN. At the same time, the dislocation density in the indented Au crystal is tracked by monitoring the Au Laue spots eventually resulting in complete stress‐dislocation density curves. The precise measurement of both stress and strain is indispensable for the accurate characterization of mechanical properties, which is however difficult in crowded environments. Here, the force measurement with a resolution of 90 nN is realized by in situ monitoring the AFM cantilever deflection by Laue microdiffraction during nano‐indentation and simultaneously measuring the dislocation density in the indented gold crystal.

We present a combination of µLaue X-ray diffraction and X-ray excited optical luminescence (XEOL) techniques to map local strain, orientation, and light emission in metalorganic vapor phase epitaxy (MOVPE) core-shell InGaN/GaN multiple quantum wells (MQW) wires dispersed on silicon substrates. The components of the deviatoric strain tensor averaged along the beam footprint were quantified with a measurement precision better than 9 × 10⁻⁵ and an accuracy of approximately 4 × 10⁻⁴. This measurement quality is achieved by carefully calibrating the analysis chain with a Ge crystal and verifying it with measurements of the unstrained Si substrate reference. The µLaue mapping of the components of the deviatoric strain confirms the high crystal quality and the impact of the MQW shell grown only in the upper part of the GaN core, as evidenced by the local variations of the full width at half maximum of the diffraction peaks and of the lattice rotation tensor. The two deviatoric tensors of the GaN core and InGaN/GaN shell can be measured independently and are in quantitative agreement with three-dimensional finite element method (FEM) simulations. The structural information is correlated with XEOL measurements, whose spectral analysis reveals the main contributions to light emission: the major blue MQW emission from the m-plane at the top of the wires, with a gradient varying from 406 nm at the top of the MQW to 397 nm at the bottom, with a secondary emission of a semipolar r-plane facet at 470 nm; the nearband-edge GaN signal at 363 nm; and the usual yellow defect-band luminescence, centered at 560 nm. The paper also highlights the potential of these techniques to obtain statistics on semiconductor heterostructures and their automation capabilities for measurements and analysis.

Synchrotron Laue microdiffraction and digital image correlation measurements were coupled to track the elastic strain field (or stress field) and the total strain field near a general grain boundary in a bent bicrystal. A 316L stainless steel bicrystal was deformed in situ into the elasto-plastic regime using a four-point bending setup. The test was then simulated using finite elements with a crystal plasticity model comprising internal variables (dislocation densities on discrete slip systems). The predictions of the model are compared with both the total strain field and the elastic strain field obtained experimentally. While activated slip systems and total strains are reasonably well predicted, elastic strains appear overestimated next to the grain boundary. This suggests that conventional crystal plasticity models need improvement to correctly model stresses at grain boundaries.

Gaseous nitriding of Ni-4 wt pct Ti alloy plates led to the development of double expanded austenite ( γ N1 and γ N2 ) at the surface of the nitride plates. Grazing-incidence X-ray diffraction analysis demonstrated that the component γ N1 is located close to the surface and the component γ N2 is located at a certain depth below the specimen surface, in correspondence with a layered character of the nitrided zone beneath the surface as revealed by optical microscopy. Electron probe microanalysis, atom probe tomography, and Laue microdiffraction analysis did not reveal a significant difference in nitrogen content of the γ N1 and γ N2 sublayers. By X-ray diffraction stress analysis it was shown that the only significant differences of the two expanded austenite layers is a pronounced difference in compressive stress parallel to the surface: the γ N1 layer is subjected to a huge compressive stress, as large as a few GPa, whereas a relatively modest stress prevails in the γ N2 layer.

During the last decade pulverized rocks have been described on outcrops along large active faults and attributed to damage related to a propagating seismic rupture front. Questions remain concerning the maximal lateral distance from the fault plane and maximal depth for dynamic damage to be imprinted in rocks. In order to document these questions, a representative core sample of granodiorite located 51.3 m from the Nojima fault (Japan) that was drilled after the Hyogo-ken Nanbu (Kobe) earthquake is studied by using electron backscattered diffraction (EBSD) and high-resolution X-ray Laue microdiffraction. Although located outside of the Nojima damage fault zone and macroscopically undeformed, the sample shows pervasive microfractures and local fragmentation. These features are attributed to the first stage of seismic activity along the Nojima fault characterized by laumontite as the main sealing mineral. EBSD mapping was used in order to characterize the crystallographic orientation and deformation microstructures in the sample, and X-ray microdiffraction was used to measure elastic strain and residual stresses on each point of the mapped quartz grain. Both methods give consistent results on the crystallographic orientation and show small and short wavelength misorientations associated with laumontite-sealed microfractures and alignments of tiny fluid inclusions. Deformation microstructures in quartz are symptomatic of the semi-brittle faulting regime, in which low-temperature brittle plastic deformation and stress-driven dissolution-deposition processes occur conjointly. This deformation occurred at a 3.7–11.1 km depth interval as indicated by the laumontite stability domain. Residual stresses are calculated from deviatoric elastic strain tensor measured using X-ray Laue microdiffraction using the Hooke's law. The modal value of the von Mises stress distribution is at 100 MPa and the mean at 141 MPa. Such stress values are comparable to the peak strength of a deformed granodiorite from the damage zone of the Nojima fault. This indicates that, although apparently and macroscopically undeformed, the sample is actually damaged. The homogeneously distributed microfracturing of quartz is the microscopically visible imprint of this damage and suggests that high stresses were stored in the whole sample and not only concentrated on some crystal defects. It is proposed that the high residual stresses are the sum of the stress fields associated with individual dislocations and dislocation microstructures. These stresses are interpreted to be originated from the dynamic damage related to the propagation of rupture fronts or seismic waves at a depth where confining pressure prevented pulverization. Actually, M6 to M7 earthquakes occurred during the Paleocene on the Nojima fault and are good candidates for inducing this dynamic damage. The high residual stresses and the deformation microstructures would have contributed to the widening of the damaged fault zone with additional large earthquakes occurring on the Nojima fault.

Synchrotron Laue microdiffraction and Digital Image Correlation measurements were coupled to track the elastic strain field (or stress field) and the total strain field near a general grain boundary in a bent bicrystal. A 316L stainless steel bicrystal was deformed in situ into the elasto-plastic regime with a four-point bending setup. The test was then simulated using finite elements with a crystal plasticity model comprising internal variables (dislocation densities on discrete slip systems). The predictions of the model have been compared with both the total strain field and the elastic strain field obtained experimentally. While activated slip systems and total strains are reasonably well predicted, elastic strains appear overestimated next to the grain boundary. This suggests that conventional crystal plasticity models need improvement to correctly model stresses at grain boundaries.

The growth and annealing behavior of strongly twinned homoepitaxial films on Ir(111) has been investigated by scanning tunneling microscopy, low energy electron diffraction and surface X-ray diffraction. In situ surface X-ray diffraction during and after film growth turned out to be an efficient tool for the determination of twin fractions in multilayer films and to uncover the nature of side twin boundaries. The annealing of the twin structures is shown to take place in a two step process, reducing first the length of the boundaries between differently stacked areas and only then the twins themselves. A model for the structure of the side twin boundaries is proposed which is consistent with both the scanning tunneling microscopy and surface X-ray diffraction data.