Periodically poled KTA crystal investigated using coherent X-ray beams

2000 ◽  
Vol 33 (4) ◽  
pp. 1149-1153 ◽  
Author(s):  
P. Pernot-Rejmánková ◽  
P. A. Thomas ◽  
P. Cloetens ◽  
F. Lorut ◽  
J. Baruchel ◽  
...  
Keyword(s):  
Phase Difference ◽  
Domain Walls ◽  
Structural Information ◽  
Periodically Poled ◽  
Synchrotron Source ◽  
X Ray ◽  
Diffracted Waves ◽  
Coherent Beams ◽  
Diffraction Imaging ◽  
The Difference

The distribution of inverted ferroelectric domains on the surface and within the bulk of a periodically poled KTA (KTiOAsO4) single crystal has been observed using a simple X-ray diffraction imaging setup which takes advantage of the highly coherent beams available at a third-generation synchrotron source, such as the ESRF. This technique allows one to reveal the phase difference between the waves that are Bragg diffracted from adjacent domainsviafree-space propagation (Fresnel diffraction). The phase difference of the diffracted waves is mainly produced by the difference in phases of the structure factors involved, and contains precise structural information about the nature of the domain walls.

2D real space visualization of d values in polycrystalline bulk materials of different hardness

2021 ◽  
Vol 54 (2) ◽  
pp. 597-603
Author(s):  
Mari Mizusawa ◽  
Kenji Sakurai
Keyword(s):  
Lattice Distortion ◽  
Structural Information ◽  
Hardness Test ◽  
Real Space ◽  
Polycrystalline Materials ◽  
X Rays ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Imaging ◽  
D Values

Conventional X-ray diffraction measurements provide some average structural information, mainly on the crystal structure of the whole area of the given specimen, which might not be very uniform and may include different crystal structures, such as co-existing crystal phases and/or lattice distortion. The way in which the lattice plane changes due to strain also might depend on the position in the sample, and the average information might have some limits. Therefore, it is important to analyse the sample with good lateral spatial resolution in real space. Although various techniques for diffraction topography have been developed for single crystals, it has not always been easy to image polycrystalline materials. Since the late 1990s, imaging technology for fluorescent X-rays and X-ray absorption fine structure has been developed via a method that does not scan either a sample or an X-ray beam. X-ray diffraction imaging can be performed when this technique is applied to a synchrotron radiation beamline with a variable wavelength. The present paper reports the application of X-ray diffraction imaging to bulk steel materials with varying hardness. In this study, the distribution of lattice distortion of hardness test blocks with different hardness was examined. Via this 2D visualization method, the grains of the crystals with low hardness are large enough to be observed by X-ray diffraction contrast in real space. The change of the d value in the vicinity of the Vickers mark has also been quantitatively evaluated.

scholarly journals Estimating signal and noise of time-resolved X-ray solution scattering data at synchrotrons and XFELs

2020 ◽  
Vol 27 (3) ◽  
pp. 633-645
Author(s):  
Jungmin Kim ◽  
Jong Goo Kim ◽  
Hosung Ki ◽  
Chi Woo Ahn ◽  
Hyotcherl Ihee
Keyword(s):  
Quantum Noise ◽  
Structural Information ◽  
Signal To Noise Ratio ◽  
Liquid Solution ◽  
Solution Phase ◽  
Scattering Data ◽  
Time Resolved ◽  
X Ray ◽  
The Future ◽  
The Difference

Elucidating the structural dynamics of small molecules and proteins in the liquid solution phase is essential to ensure a fundamental understanding of their reaction mechanisms. In this regard, time-resolved X-ray solution scattering (TRXSS), also known as time-resolved X-ray liquidography (TRXL), has been established as a powerful technique for obtaining the structural information of reaction intermediates and products in the liquid solution phase and is expected to be applied to a wider range of molecules in the future. A TRXL experiment is generally performed at the beamline of a synchrotron or an X-ray free-electron laser (XFEL) to provide intense and short X-ray pulses. Considering the limited opportunities to use these facilities, it is necessary to verify the plausibility of a target experiment prior to the actual experiment. For this purpose, a program has been developed, referred to as S-cube, which is short for a Solution Scattering Simulator. This code allows the routine estimation of the shape and signal-to-noise ratio (SNR) of TRXL data from known experimental parameters. Specifically, S-cube calculates the difference scattering curve and the associated quantum noise on the basis of the molecular structure of the target reactant and product, the target solvent, the energy of the pump laser pulse and the specifications of the beamline to be used. Employing a simplified form for the pair-distribution function required to calculate the solute–solvent cross term greatly increases the calculation speed as compared with a typical TRXL data analysis. Demonstrative applications of S-cube are presented, including the estimation of the expected TRXL data and SNR level for the future LCLS-II HE beamlines.

Two- and Three-Beam X-ray Diffraction Imaging of Domains in Magnetite

1998 ◽  
Vol 31 (5) ◽  
pp. 726-732
Author(s):  
C. Medrano ◽  
F. Heyroth ◽  
M. Schlenker ◽  
J. Baruchel ◽  
J. Espeso
Keyword(s):  
Synchrotron Radiation ◽  
Room Temperature ◽  
X Ray Diffraction ◽  
Large Crystal ◽  
Angular Sensitivity ◽  
X Ray ◽  
Diffraction Imaging ◽  
The Difference ◽  
Topographic Imaging ◽  
Radiation Beams

The X-ray diffraction topographic imaging process for ferrimagnetic domains in magnetite Fe3O4at room temperature is investigated, in two- and three-beam cases, for incident synchrotron radiation beams differing in angular divergence and energy spread. In the usual two-beam configuration, domain or wall contrast is obtained from the difference in Bragg conditions, or from the slight difference in the direction of the beams diffracted by neighbouring domains, revealed by the large crystal-to-film distance that can be used at a third-generation synchrotron radiation facility. A three-beamUmweganregungcase involving the weak 171 and the strong 131 reflections shows unusual domain contrast on the 171 topographs, even on images involving energy or angle integration; this contrast is particularly evident on white-beam topographs. The high angular sensitivity this implies is associated with the difference in dispersion relation between the two reflections.

Investigation by coherent X-ray section topography of ferroelectric domain behaviour as a function of temperature in periodically poled Rb:KTP

2011 ◽  
Vol 44 (3) ◽  
pp. 462-466 ◽  
Author(s):  
Fabio Masiello ◽  
Tamzin A. Lafford ◽  
Petra Pernot ◽  
José Baruchel ◽  
Dean S. Keeble ◽  
...  
Keyword(s):  
Curie Temperature ◽  
Ferroelectric Domain ◽  
Potassium Titanyl Phosphate ◽  
X Ray Diffraction ◽  
Periodically Poled ◽  
X Ray ◽  
Ferroelectric Domains ◽  
Diffraction Imaging ◽  
Section Topography

The behaviour of ferroelectric domains at high temperatures near the Curie temperature in a periodically poled rubidium-doped potassium titanyl phosphate crystal (Rb:KTP) has been studied by Bragg–Fresnel X-ray diffraction imagingin situusing a compact coherence-preserving furnace. The development and partial disappearance of the inverted domain structure as the temperature increases has been successfully modelled, and is explained by invoking a built-in electric field produced under heating in a low vacuum by out-diffusion of atoms from the sample.

Temperature evolution of Fe–27Ga structure: comparison of in situ X-ray and neutron diffraction studies

2020 ◽  
Vol 53 (5) ◽  
pp. 1343-1352 ◽  
Author(s):  
Ivan A. Bobrikov ◽  
Nataliya Yu. Samoylova ◽  
Sergey V. Sumnikov ◽  
Olga Yu. Ivanshina ◽  
Ekaterina A. Korneeva ◽  
...  
Keyword(s):  
Neutron Diffraction ◽  
Structural Information ◽  
Bulk Sample ◽  
Alloy Sample ◽  
X Rays ◽  
Structure Comparison ◽  
X Ray ◽  
The Difference ◽  
Heating Up

Comparative in situ X-ray and neutron diffraction studies of the phase transitions in a high magnetostriction Fe–27Ga alloy sample have been performed, with heating up to 850°C and subsequent cooling to room temperature. Different structural information (phase content, phase-transition temperatures, unit-cell behaviour) is obtained for the bulk sample and its surface, and this fact is discussed here in terms of the difference between the scattering properties of X-rays and neutrons. In particular, a gallium-deficient phase with A2-type structure was found on the surface of the sample. The results demonstrate that conventional X-ray diffraction methods are insufficient for precise structural analysis of bulk samples of galfenols and cannot be used alone to build their phase diagrams.

Elastic strain gradients and x-ray line broadening effects as a function of temperature in aluminum thin films on silicon

1994 ◽  
Vol 9 (2) ◽  
pp. 328-335 ◽  
Author(s):  
Ramnath Venkatraman ◽  
Paul R. Besser ◽  
John C. Bravman ◽  
Sean Brennan
Keyword(s):  
Thin Films ◽  
Elastic Strain ◽  
Large Strain ◽  
Grazing Incidence ◽  
Film Stress ◽  
Line Broadening ◽  
Synchrotron Source ◽  
Strain Gradients ◽  
X Ray ◽  
The Difference

Grazing incidence x-ray scattering (GIXS) with a synchrotron source was used to measure elastic strain gradients as a function of temperature in aluminum and aluminum alloy thin films of different thicknesses on silicon. The stresses in the films are induced as a result of the difference in thermal expansion coefficient between film and substrate. Disregarding minor deviations at the surface, it is shown that there are no gross strain gradients in these films in the range of temperatures (between room temperature and 400 °C) considered. Significant x-ray line broadening effects were observed, suggesting an accumulation of dislocations on cooling the films and their annealing out as the films were being reheated. The variation of the dislocation density during thermal cycling compares well in nature with that of the concurrent variation in film stress, indicating that large strain hardening effects contribute toward the film flow stress.

Coherent diffraction imaging: consistency of the assembled three-dimensional distribution

2016 ◽  
Vol 72 (4) ◽  
pp. 459-464 ◽  
Author(s):  
Miklós Tegze ◽  
Gábor Bortel
Keyword(s):  
Structural Information ◽  
Three Dimensional ◽  
Atomic Scale ◽  
Short Pulses ◽  
X Ray ◽  
Coherent Diffraction Imaging ◽  
Imaging Experiment ◽  
Dimensional Distribution ◽  
Diffraction Imaging ◽  
Diffraction Patterns

The short pulses of X-ray free-electron lasers can produce diffraction patterns with structural information before radiation damage destroys the particle. From the recorded diffraction patterns the structure of particles or molecules can be determined on the nano- or even atomic scale. In a coherent diffraction imaging experiment thousands of diffraction patterns of identical particles are recorded and assembled into a three-dimensional distribution which is subsequently used to solve the structure of the particle. It is essential to know, but not always obvious, that the assembled three-dimensional reciprocal-space intensity distribution is really consistent with the measured diffraction patterns. This paper shows that, with the use of correlation maps and a single parameter calculated from them, the consistency of the three-dimensional distribution can be reliably validated.

scholarly journals Coherent Bragg nanodiffraction at the hard X-ray Nanoprobe beamline

2014 ◽  
Vol 372 (2010) ◽  
pp. 20130118 ◽  
Author(s):  
S. O. Hruszkewycz ◽  
M. V. Holt ◽  
J. Maser ◽  
C. E. Murray ◽  
M. J. Highland ◽  
...  
Keyword(s):  
Bragg Diffraction ◽  
Complex Materials ◽  
Fringe Visibility ◽  
X Ray ◽  
Coherent Diffraction Imaging ◽  
Coherent Beams ◽  
Diffraction Imaging ◽  
Diffraction Patterns ◽  
Scattering Volume

Bragg coherent diffraction with nanofocused hard X-ray beams provides unique opportunities for quantitative in situ studies of crystalline structure in nanoscale regions of complex materials and devices by a variety of diffraction-based techniques. In the case of coherent diffraction imaging, a major experimental challenge in using nanoscale coherent beams is maintaining a constant scattering volume such that coherent fringe visibility is maximized and maintained over the course of an exposure lasting several seconds. Here, we present coherent Bragg diffraction patterns measured from different nanostructured thin films at the Sector 26 Nanoprobe beamline at the Advanced Photon Source and demonstrate that with nanoscale positional control, coherent diffraction patterns can be measured with source-limited fringe visibilities more than 50% suitable for imaging by coherent Bragg ptychography techniques.

scholarly journals Energy Dispersive X-Ray Diffraction Imaging

2013 ◽  
Vol 772 ◽  
pp. 21-25 ◽  
Author(s):  
Jörn Donges ◽  
André Rothkirch ◽  
Thomas Wroblewski ◽  
Aniouar Bjeoumikhov ◽  
Oliver Scharf ◽  
...  
Keyword(s):  
Spatial Information ◽  
Structural Information ◽  
Reciprocal Space ◽  
Energy Dispersive ◽  
Polycrystalline Materials ◽  
X Ray Diffraction ◽  
X Ray ◽  
Area Detector ◽  
Diffraction Imaging ◽  
Position Sensitive

Position resolved structural information from polycrystalline materials is usually obtained via micro beam techniques illuminating only a single spot of the specimen. Multiplexing in reciprocal space is achieved either by the use of an area detector or an energy dispersive device. Alternatively spatial information may be obtained simultaneously from a large part of the sample by using an array of parallel collimators between the sample and a position sensitive detector which suppresses crossfire of radiation scattered at different positions in the sample. With the introduction of an X-ray camera based on an energy resolving area detector (pnCCD) we could combine this with multiplexing in reciprocal space.

scholarly journals The Effect of the Anomalous Absorption on the Diffraction Contrast on 90° Bloch Walls

1973 ◽  
Vol 28 (5) ◽  
pp. 639-642
Author(s):  
M. Polcarová
Keyword(s):  
Domain Walls ◽  
Plate Thickness ◽  
Anomalous Absorption ◽  
X Ray ◽  
Diffraction Contrast ◽  
Ferromagnetic Domain ◽  
Normal Absorption ◽  
The Difference ◽  
Theoretical Results ◽  
Very High

The diffraction contrast produced by 90° ferromagnetic domain walls in X-ray transmission topographs is calculated. Two cases are considered: very low and very high normal absorption. The results indicate that the difference in contrast on walls having opposite signs of lattice tilt is due to the anomalous absorption and depends on the magnitude of normal absorption. These theoretical results are in agreement with the contrast observations in X-ray transmission topographs taken from Fe-3 wt%Si single crystal samples using different plate thickness and different radiations.

Sign in / Sign up

Export Citation Format

Share Document