Study of dislocations in AlN single-crystal using bright-field synchrotron x-ray topography under a multiple-beam diffraction condition

2020 ◽  
Vol 117 (9) ◽  
pp. 092102 ◽  
Author(s):  
Yongzhao Yao ◽  
Yoshiyuki Tsusaka ◽  
Yukari Ishikawa ◽  
Yoshihiro Sugawara ◽  
Yu Fujita ◽  
...  
2021 ◽  
Vol 54 (3) ◽  
Author(s):  
Zheng Tang ◽  
Lirong Zheng ◽  
Shengqi Chu ◽  
Pengfei An ◽  
Xianrong Huang ◽  
...  

On the basis of rigorous dynamical-theory calculations, a complete X-ray polarization-switch effect of silicon crystals at the exact multiple-beam diffraction condition is demonstrated. The underlying physical mechanism of this unique phenomenon can be revealed using a simple multiple-wave propagation and interference model. The constructive and destructive interference of the multiple detoured-diffraction beams along the direction of the primary diffracted beam directly leads to the complete polarization switch. This phenomenon can be realized using both synchrotron and laboratory X-ray sources at many discrete wavelengths, and used to design a novel crystal-based polarizer to achieve a 90° polarization rotation.


1992 ◽  
Vol 63 (1) ◽  
pp. 911-913 ◽  
Author(s):  
M. Hagelstein ◽  
S. Cunis ◽  
R. Frahm ◽  
P. Rabe

Crystals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1561
Author(s):  
Nataliya Klimova ◽  
Irina Snigireva ◽  
Anatoly Snigirev ◽  
Oleksandr Yefanov

The highest-quality X-ray optics can be made of single-crystal materials such as silicon, germanium, or, even better, diamond. Unfortunately, such X-ray optics have one drawback: diffraction losses or the “glitch effect”. This effect manifests itself as follows: at some energies of X-rays, the intensity of the transmitted beam drops due to the fact that some crystalline planes have satisfied the diffraction condition. Diffraction losses are usually observed in spectroscopic experiments when the energy of the X-rays changes in a certain range. However, this effect might also influence any experiment using X-rays, especially at higher energies. In this paper, we propose a method to overcome the glitch problem in transmissive optics. This is achieved using small rotations of the optical element. We describe the algorithm for “glitch-free” measurements in detail and the theory behind it.


2002 ◽  
Vol 35 (1) ◽  
pp. 69-74 ◽  
Author(s):  
S. L. Morelhão ◽  
L. H. Avanci ◽  
A. A. Quivy ◽  
E. Abramof

The observation of a new X-ray scattering process with synchrotron radiation is reported. The phenomenon is analogous to three-beam diffraction in a single crystal; however, the features in the azimuthal scans are provided by superlattice-satellite reflections instead of bulk reflections. These features were named effective satellites and they are observed over the ordinary satellite reflections as a function of the azimuthal angle. Their occurrences have been monitored in completely different superlattices by mapping the incidence and azimuthal angles of the incident X-ray beam. Effects of structural parameters of the superlattices on the effective satellites as well as the information that can be extracted by measuring their positions are discussed.


2016 ◽  
Vol 49 (5) ◽  
pp. 1653-1658 ◽  
Author(s):  
Y.-H. Wu ◽  
Y.-Y. Chang ◽  
Y.-W. Tsai ◽  
S.-L. Chang

Detailed considerations of how to construct inclined-incidence hard X-ray resonators are presented. Owing to the symmetry of the crystals used, the Bragg back reflection usually employed in normal-incidence two- and multi-plate resonators to reflect the X-ray beam is often accompanied by unavoidable multiple-beam diffraction, and thus the reflectivity and cavity finesse are quite low. In contrast, crystal-based Fabry–Perot (FP) resonators at inclined incidence utilize multiple-beam diffraction to excite the back reflection inside the resonator to generate FP resonance with high efficiency, while avoiding the incident beam suffering from crystal absorption. The useful characteristics of inclined-incidence resonators are derived from numerical calculations based on the inclined-incidence diffraction geometry and the dynamical theory. Experimental results with Laue inclined incidence are in accordance with the simulation. The sub-millielectronvolt energy resolution and ultra-high efficiency of the transmission spectrum of the proposed resonators are also described.


2016 ◽  
Vol 87 (2) ◽  
pp. 023701 ◽  
Author(s):  
Y. Tsusaka ◽  
S. Takeda ◽  
H. Takano ◽  
K. Yokoyama ◽  
Y. Kagoshima ◽  
...  

2015 ◽  
Vol 71 (4) ◽  
pp. 460-466 ◽  
Author(s):  
Po-Yu Liao ◽  
Wen-Chung Liu ◽  
Chih-Hao Cheng ◽  
Yi-Hua Chiu ◽  
Ying-Yu Kung ◽  
...  

This paper reports temperature- and energy-dependent phase shifts of resonant multiple-beam X-ray diffraction in germanium crystals, involving forbidden (002) and weak (222) reflections. Phase determination based on multiple-beam diffraction is employed to estimate phase shifts from (002)-based \{(002)(375)(37\overline{3})\} four-beam cases and (222)-based \{ (222)(\overline{5}3\overline{3})\} three-beam cases in the vicinity of the GeKedge for temperatures from 20 K up to 300 K. The forbidden/weak reflections enhance the sensitivity of measuring phases at resonance. At room temperature, the resonance triplet phases reach a maximum of 8° for the four-beam cases and −19° for the three-beam cases. It is found that the peak intensities and triplet phases obtained from the (002) four-beam diffraction are related to thermal motion induced anisotropy and anomalous dispersion, while the (222) three-beam diffraction depends on the aspherical covalent electron distribution and anomalous dispersion. However, the electron–phonon interaction usually affects the forbidden reflections with increasing temperatures and seems to have less effect on the resonance triplet phase shifts measured from the (002) four-beam diffraction. The resonance triplet phase shifts of the (222) three-beam diffractionversustemperature are also small.


2014 ◽  
Vol 47 (5) ◽  
pp. 1716-1721 ◽  
Author(s):  
Xian-Rong Huang ◽  
Quanjie Jia ◽  
Michael Wieczorek ◽  
Lahsen Assoufid

The interesting phenomenon of continuous multiple-beam diffraction (MBD) occurring within special crystallographic planes of cubic structures is illustrated for any Bragg angles of the primary reflection. On the one hand, this effect must be avoided in crystal-based X-ray optics or general crystal diffraction experiments that are designed to utilize two-beam diffraction mechanisms, since the MBD process can significantly reduce the diffraction efficiency and the monochromatization quality. On the other hand, the continuous MBD mechanism may have unique practical applications, with the advantage that it can be activated at arbitrary X-ray wavelengths by simply adjusting the azimuthal angle of the primary reflection. A simple mathematical procedure for determining the continuous MBD planes of any primary reflections is developed for optimization of X-ray monochromator designs and for general X-ray characterization of (pseudo)cubic structure crystals using MBD.


2014 ◽  
Vol 105 (18) ◽  
pp. 181903 ◽  
Author(s):  
Xian-Rong Huang ◽  
Ru-Wen Peng ◽  
Thomas Gog ◽  
D. P. Siddons ◽  
Lahsen Assoufid

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