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Title: Simulations of Bragg diffraction of a focused x-ray beam by a single crystal with an epitaxial layer

Abstract

The Bragg case diffraction of a narrow x-ray beam in a multilayer crystal is studied theoretically. The beam produced by a parabolic refractive lens is Bragg reflected by a crystalline sample and a spatial distribution of the intensity is recorded by a detector placed at the focus of the lens. This x-ray optical scheme represents a topographic technique which is extremely sensitive to a depth variation of a crystalline structure. Simulations of the intensity pattern were performed by using a computational technique based on a convolution of individual propagators by performing a double fast Fourier transform procedure. It was shown that each interface in a multilayer crystal can be observed on the intensity pattern with a contrast depending on the incident angle. Thus, by recording a series of images at different angles, valuable depth sensitive structural information can be obtained.

Authors:
 [1];  [2]
  1. Russian Research Center 'Kurchatov Institute', 123182, Moscow (Russian Federation)
  2. Cornell High Energy Synchrotron Source, Cornell University, Ithaca, New York 14853 (United States)
Publication Date:
OSTI Identifier:
20951529
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 22; Other Information: DOI: 10.1103/PhysRevB.75.224119; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BEAMS; BRAGG REFLECTION; CRYSTALLOGRAPHY; DEPTH; EPITAXY; FOURIER TRANSFORMATION; IMAGES; LAYERS; OPTICS; SIMULATION; SPATIAL DISTRIBUTION; X-RAY DIFFRACTION

Citation Formats

Kohn, V. G., and Kazimirov, A. Simulations of Bragg diffraction of a focused x-ray beam by a single crystal with an epitaxial layer. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.224119.
Kohn, V. G., & Kazimirov, A. Simulations of Bragg diffraction of a focused x-ray beam by a single crystal with an epitaxial layer. United States. doi:10.1103/PHYSREVB.75.224119.
Kohn, V. G., and Kazimirov, A. Fri . "Simulations of Bragg diffraction of a focused x-ray beam by a single crystal with an epitaxial layer". United States. doi:10.1103/PHYSREVB.75.224119.
@article{osti_20951529,
title = {Simulations of Bragg diffraction of a focused x-ray beam by a single crystal with an epitaxial layer},
author = {Kohn, V. G. and Kazimirov, A.},
abstractNote = {The Bragg case diffraction of a narrow x-ray beam in a multilayer crystal is studied theoretically. The beam produced by a parabolic refractive lens is Bragg reflected by a crystalline sample and a spatial distribution of the intensity is recorded by a detector placed at the focus of the lens. This x-ray optical scheme represents a topographic technique which is extremely sensitive to a depth variation of a crystalline structure. Simulations of the intensity pattern were performed by using a computational technique based on a convolution of individual propagators by performing a double fast Fourier transform procedure. It was shown that each interface in a multilayer crystal can be observed on the intensity pattern with a contrast depending on the incident angle. Thus, by recording a series of images at different angles, valuable depth sensitive structural information can be obtained.},
doi = {10.1103/PHYSREVB.75.224119},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 22,
volume = 75,
place = {United States},
year = {Fri Jun 01 00:00:00 EDT 2007},
month = {Fri Jun 01 00:00:00 EDT 2007}
}
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