Dynamical diffraction effects on higher-order laue zone lines in CBED patterns of semiconductors

This article reports a theoretical study on the reconstruction artefacts in Bragg coherent diffractive imaging caused by dynamical diffraction effects. It is shown that, unlike the absorption and refraction effects that can be corrected after reconstruction, dynamical diffraction effects have profound impacts on both the amplitude and the phase of the reconstructed complex object, causing strong artefacts. At the dynamical diffraction limit, the reconstructed shape is no longer correct, as a result of the strong extinction effect. Simulations for hemispherical particles of different sizes show the type, magnitude and extent of the dynamical diffraction artefacts, as well as the conditions under which they are negligible.

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Dynamical diffraction effects in STEM orbital angular momentum resolved electron energy-loss magnetic chiral dichroism

Physical Review B ◽

10.1103/physrevb.102.184420 ◽

2020 ◽

Vol 102 (18) ◽

Author(s):

Matteo Zanfrognini ◽

Enzo Rotunno ◽

Jan Rusz ◽

Rafal E. Dunin Borkowski ◽

Ebrahim Karimi ◽

...

Keyword(s):

Angular Momentum ◽

Energy Loss ◽

Electron Energy ◽

Orbital Angular Momentum ◽

Dynamical Diffraction ◽

Diffraction Effects ◽

Electron Energy Loss

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X-ray third-order nonlinear plane-wave Bragg-case dynamical diffraction effects in a perfect crystal

Journal of Synchrotron Radiation ◽

10.1107/s1600577515017804 ◽

2015 ◽

Vol 22 (6) ◽

pp. 1410-1418 ◽

Cited By ~ 4

Author(s):

Minas K. Balyan

Keyword(s):

Analytical Solution ◽

Perfect Crystal ◽

Total Reflection ◽

Numerical Calculations ◽

Third Order ◽

Dynamical Diffraction ◽

X Ray ◽

Infinite Crystal ◽

Nonlinear Plane ◽

Diffraction Effects

Two-wave symmetric Bragg-case dynamical diffraction of a plane X-ray wave in a crystal with third-order nonlinear response to the electric field is considered theoretically. For certain diffraction conditions for a non-absorbing perfect semi-infinite crystal in the total reflection region an analytical solution is found. For the width and for the center of the total reflection region expressions on the intensity of the incidence wave are established. It is shown that in the nonlinear case the total reflection region exists below a maximal intensity of the incidence wave. With increasing intensity of the incidence wave the total reflection region's center moves to low angles and the width decreases. Using numerical calculations for an absorbing semi-infinite crystal, the behavior of the reflected wave as a function of the intensity of the incidence wave and of the deviation parameter from the Bragg condition is analyzed. The results of numerical calculations are compared with the obtained analytical solution.

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Dynamical diffraction effects

Diffraction Physics ◽

10.1016/b978-044482218-5/50011-0 ◽

1995 ◽

pp. 189-207 ◽

Cited By ~ 1

Author(s):

JOHN M. COWLEY

Keyword(s):

Dynamical Diffraction ◽

Diffraction Effects

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X-Ray Dynamical Diffraction in Powder Samples with Time-Dependent Particle Size Distributions

MRS Advances ◽

10.1557/adv.2019.445 ◽

2019 ◽

Vol 5 (29-30) ◽

pp. 1585-1591 ◽

Cited By ~ 1

Author(s):

Adriana Valério ◽

Sérgio L. Morelhão ◽

Alex J. Freitas Cabral ◽

Márcio M. Soares ◽

Cláudio M. R. Remédios

Keyword(s):

Particle Size ◽

Single Phase ◽

Diffraction Peak ◽

Time Dependent ◽

Peak Width ◽

Dynamical Diffraction ◽

X Ray ◽

Integrated Intensity ◽

Diffraction Effects

ABSTRACTIn situ X-ray diffraction is one of the most useful tools for studying a variety of processes, among which crystallization of nanoparticles where phase purity and size control are desired. Growth kinetics of a single phase can be completely resolved by proper analysis of the diffraction peaks as a function of time. The peak width provides a parameter for monitoring the time evolution of the particle size distribution (PSD), while the peak area (integrated intensity) is directly related to the whole diffracting volume of crystallized material in the sample. However, to precisely describe the growth kinetics in terms of nucleation and coarsening, the correlation between PSD parameters and diffraction peak widths has to be established in each particular study. Corrections in integrated intensity values for physical phenomena such as variation in atomic thermal vibrations and dynamical diffraction effects have also to be considered in certain cases. In this work, a general correlation between PSD median value and diffraction peak width is deduced, and a systematic procedure to resolve time-dependent lognormal PSDs from in situ XRD experiments is described in details. A procedure to correct the integrated intensities for dynamical diffraction effects is proposed. As a practical demonstration, this analytical procedure has been applied to the single-phase crystallization process of bismuth ferrite nanoparticles.

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