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Raw data for "Imaging Cu2O nanocube hollowing in solution by quantitative in situ X-ray ptychography" Ptychographic data sets The file "raw_data_ptychography.zip" contains one HDF5 archive for each ptychographic scan. The archives are structured as follows: section experiment: identifiers of the lightsource, beamline, beamtime, session number, and scan number section measured: N diffraction patterns of size 512x512 px N scan positions in mm one detector mask of size 512x512 px slice separation in mm for multi slice reconstruction section parameters: distance between sample and detector in mm pixel size of detector in mm photon energy in keV cropping of diffraction patterns in px used during reconstruction The following list shows the scan numbers with their corresponding reaction times and slice separations for the in situ series measured at beamline P06 at 15.25 keV. scan number slice distance, mm reaction time, h 232 1 0.20 233 1 0.56 234 1 0.92 235 1 1.27 236 1 1.63 237 1 2.01 238 0.98 2.36 239 0.96 2.72 240 0.94 3.08 241 0.9 3.43 242 0.88 3.83 243 0.86 4.19 244 0.84 4.54 245 0.82 4.90 246 0.82 5.26 247 0.82 5.63 248 0.8 5.98 249 0.8 6.34 250 0.8 6.70 251 0.78 7.05 252 0.78 7.43 253 0.78 7.79 254 0.76 8.15 255 0.76 8.50 256 0.76 8.86 257 0.74 9.23 258 0.74 9.58 259 0.72 9.94 260 0.72 10.30 261 0.7 10.65 262 0.68 11.07 263 0.66 11.42 264 0.64 11.78 266 0.62 12.17 267 0.6 12.53 268 0.58 12.89 269 0.56 13.24 270 0.54 13.60 271 0.52 13.99 272 0.5 14.37 273 0.46 14.72 274 0.42 15.08 275 0.4 15.44 277 0.4 15.87 278 0.4 16.22 279 0.36 16.58 280 0.3 16.93 281 0.25 17.29 282 0.25 17.68 283 0.25 18.04 289 0.2 20.45 290 0.2 21.47 Ptychographic reconstructions The file "ptychographic_reconstructions.zip" contains the ptychographic reconstructions shown in the article and supplementary information in tiff format. Stacks of images corresponding to time series: P06_15.25_keV_scans_00232-00283_entrance_window_aligned.tif P06_15.25_keV_scans_00232-00283_exit_window_aligned.tif cSAXS_8.98_keV_scans_00200-00324_aligned.tif Single images (the file name indicates the respective figure): P06_15.25_keV_scan_00289_Figure_6_a.tif P06_15.25_keV_scan_00290_Supplementary_Figure_11.tif cSAXS_8.98_keV_scan_00347_Supplementary_Figure_13_d.tif cSAXS_8.98_keV_scan_00586_Supplementary_Figure_14_a.tif SEM images The file "SEM_images.zip" contains the SEM images shown in the article and supplementary information in tiff format. The file names indicate the respective figure: Figure_5_h.tif Figure_5_i.tif Figure_6_b.tif Supplementary_Figure_14_b.tif, Acknowledgements: This work was supported by the Bundesministerium für Bildung und Forschung (BMBF) within the Röntgen-Ångström-Cluster via the project 05K2020 - 2019-06104 XStereoVision (grant no. 05K20GUA), by the European Research Council within the project LINCHPIN (grant no. 818941), and by the Cluster of Excellence "CUI: Advanced Imaging of Matter" of the Deutsche Forschungsgemeinschaft (DFG) – EXC 2056 – project ID 390715994.

Materials 14(1), 228 (tbd). doi:10.3390/ma14010228, Inhomogeneities and defects often limit the overall performance of thin-film solar cells. Therefore, sophisticated microscopy approaches are sought to characterize performance and defects at the nanoscale. Here, we demonstrate, for the first time, the simultaneous assessment of composition, structure, and performance in four-fold multi-modality. Using scanning X-ray microscopy of a Cu(In,Ga)Se$_2$ (CIGS) solar cell, we measured the elemental distribution of the key absorber elements, the electrical and optical response, and the phase shift of the coherent X-rays with nanoscale resolution. We found structural features in the absorber layer—interpreted as voids—that correlate with poor electrical performance and point towards defects that limit the overall solar cell efficiency., Published by MDPI, Basel

Journal of synchrotron radiation 25(1), 1 - 8 (2018). doi:10.1107/S1600577517015272, Wavefront errors of rotationally parabolic refractive X-ray lenses made of beryllium (Be CRLs) have been recovered for various lens sets and X-ray beam configurations. Due to manufacturing via an embossing process, aberrations of individual lenses within the investigated ensemble are very similar. By deriving a mean single-lens deformation for the ensemble, aberrations of any arbitrary lens stack can be predicted from the ensemble with \bar{\sigma} = 0.034λ. Using these findings the expected focusing performance of current Be CRLs are modeled for relevant X-ray energies and bandwidths and it is shown that a correction of aberrations can be realised without prior lens characterization but simply based on the derived lens deformation. The performance of aberration-corrected Be CRLs is discussed and the applicability of aberration-correction demonstrated over wide X-ray energy ranges., Published by IUCr, Chester

Two different multilayer Laue lens designs were made with total deposition thicknesses of 48 mu m and 53 mu m, and focal lengths of 20.0 mm and 12.5 mm at 20.0 keV, respectively. From these two multilayer systems, several lenses were manufactured for one-and two-dimensional focusing. The latter is realised with a directly bonded assembly of two crossed lenses, that reduces the distance between the lenses in the beam direction to 30 mm and eliminates the necessity of producing different multilayer systems. Characterization of lens fabrication was performed using a laboratory X-ray microscope. Focusing properties have been investigated using ptychography.

In der vorliegenden Arbeit wird die neuartige Mikroskopiemethode der Ptychographie für die Untersuchung photorefraktiver Materialien genutzt. Photorefraktive Materialien zeichnen sich durch die Generation lichtinduzierter Brechungsindexänderungen aus. Die Ptychographie bietet die Möglichkeit, neben der generierten Brechungsindexänderung im photorefraktiven Material auch die für die Generation genutzte Intensitätsverteilung des Laserstrahls zu bestimmen. Es wird sowohl die Abhängigkeit der Brechungsindexänderung von der Zeit der Generation als auch die Abhängigkeit von der Polarisation des Lasers gemessen. Durch den Vergleich der gewonnenen Werte mit einer numerischen Simulation des photorefraktiven Effekts werden mikroskopische Parameter der lichtinduzierten Ladungswanderung ermittelt. Zudem wird aus der polarisationsabhängigen ptychographischen Messung das Raumladungsfeld und die korrespondierende Ladungsdichte im Material berechnet. Die Ptychographie liefert damit einen neuen Zugang zum quantitativen Verständnis der Photorefraktivität.:1 Einleitung 2 Theoretische Vorbetrachtungen 2.1 Ptychographie 2.1.1 Messung 2.1.2 Modell und Rekonstruktion 2.1.3 Ortsauflösung 2.2 Photorefraktiver Efekt 2.2.1 Lithiumniobat - Musterbeispiel für die Photorefraktivität 2.2.2 Ein-Zentrum-Modell 2.2.3 Brechungsindexänderung 2.2.4 Hohe Intensitäten 2.3 Raumladungsfeld 2.3.1 Ableitung des Feldes aus den Messgrößen 2.3.2 Raumladungsverteilung 2.3.3 Oberflächendeformation 2.3.4 Dynamik der Ladungen und des Feldes 3 Messungen 3.1 Proben 3.1.1 Ptychographische Teststruktur 3.1.2 LiNbO3:Fe 3.2 Versuchsanordnung 3.2.1 Experimenteller Aufbau 3.2.2 Grenze der Ortsauflösung 3.2.3 Charakterisierung des Laserstrahls 3.2.4 Experimentelle Überprüfung der Näherungen 3.3 Dynamik der Brechungsindexänderung 3.4 Polarisationsabhängigkeit der Brechungsindexänderung 4 Auswertung 4.1 Dynamik des Raumladungsfeldes und der Ladungen 4.1.1 Simulation 4.1.2 Vergleich zwischen Messung und Simulation 4.1.3 Dynamik der Ladungsverteilung 4.1.4 Fazit 4.2 Berechnung des Raumladungsfeldes 4.2.1 Raumladungsfeld und Ladungsverteilung 4.2.2 Simulation 4.2.3 Asymmetrie der Ladungsverteilung 4.2.4 Fazit 5 Zusammenfassung Appendizes A Physikalische Konstanten B Tensoren für LiNbO3 C Ungenäherte Herleitung der Brechungsindexänderung D Implementierung eines iterativen Verfahrens zur Bestimmung der Dynamik des Ein-Zentrum-Modells E Quelltext der Implementierung des iterativen Verfahrens Literaturverzeichnis In the present thesis the novel microscopy technique of ptychography is applied to the investigation of photorefractive materials. Photorefractive materials exhibit a change of the refractive index due to the exposure to light. The method of ptychography determines the refractive index change of the material together with the intensity distribution of the laser beam that was used for its generation. In one part of the experiment the time dependence of the refractive index change versus the generation time is investigated, in the other part of the experiment the dependence of the refractive index change to the polarisation of the laser beam is examined. Microscopic parameters of the photorefractive charge migration are determined with the utilisation of a numerical simulation of the photorefractive effect and its comparison with the measurement. Finally, the whole space charge field with the corresponding space charge density is calculated from a set of ptychographic measurements of one refractive index change with different polarisation directions of the laser. The presented experiments and their evaluation show, that the method of ptychography opens a new possibility for a quantitative understanding of the photorefractive effect.:1 Einleitung 2 Theoretische Vorbetrachtungen 2.1 Ptychographie 2.1.1 Messung 2.1.2 Modell und Rekonstruktion 2.1.3 Ortsauflösung 2.2 Photorefraktiver Efekt 2.2.1 Lithiumniobat - Musterbeispiel für die Photorefraktivität 2.2.2 Ein-Zentrum-Modell 2.2.3 Brechungsindexänderung 2.2.4 Hohe Intensitäten 2.3 Raumladungsfeld 2.3.1 Ableitung des Feldes aus den Messgrößen 2.3.2 Raumladungsverteilung 2.3.3 Oberflächendeformation 2.3.4 Dynamik der Ladungen und des Feldes 3 Messungen 3.1 Proben 3.1.1 Ptychographische Teststruktur 3.1.2 LiNbO3:Fe 3.2 Versuchsanordnung 3.2.1 Experimenteller Aufbau 3.2.2 Grenze der Ortsauflösung 3.2.3 Charakterisierung des Laserstrahls 3.2.4 Experimentelle Überprüfung der Näherungen 3.3 Dynamik der Brechungsindexänderung 3.4 Polarisationsabhängigkeit der Brechungsindexänderung 4 Auswertung 4.1 Dynamik des Raumladungsfeldes und der Ladungen 4.1.1 Simulation 4.1.2 Vergleich zwischen Messung und Simulation 4.1.3 Dynamik der Ladungsverteilung 4.1.4 Fazit 4.2 Berechnung des Raumladungsfeldes 4.2.1 Raumladungsfeld und Ladungsverteilung 4.2.2 Simulation 4.2.3 Asymmetrie der Ladungsverteilung 4.2.4 Fazit 5 Zusammenfassung Appendizes A Physikalische Konstanten B Tensoren für LiNbO3 C Ungenäherte Herleitung der Brechungsindexänderung D Implementierung eines iterativen Verfahrens zur Bestimmung der Dynamik des Ein-Zentrum-Modells E Quelltext der Implementierung des iterativen Verfahrens Literaturverzeichnis