Bloch waves and weak-beam imaging of crystals
- Heinrich H ETH Zurich, Institut fur Angewandte Physik, Switzerland.
- Kostorz G
- 2000-05-03
Published in:
- Journal of electron microscopy. - 2000
English
The influence of the number of diffracted beams on weak-beam contrast simulations of thickness contour lines and dislocation images is investigated. For large deviation parameters s(g)-->thickness contour lines from two-beam simulations are similar to those from many-beam simulations. In many-beam simulations of wedge-shaped bent samples extra thickness contour lines appear at locations with ((g)-->, 3(g)-->). These extra lines occur between the imaging condition ((g)-->, -(g)-->) and ((g)-->, 3(g)-->). Therefore, in the case of a more symmetrical imaging condition many-beam simulations are mandatory. In bent samples the contributions of different Bloch waves to weak-beam images change as a function of the imaging conditions ((g)-->, x(g)-->). Near ((g)-->, 3.5(g)-->) two Bloch waves dominate. In the case of x <3 two other Bloch waves with different wavelengths are most important for the image contrast. The 'classical' ((g)-->, 3(g)-->) weak-beam condition is not suitable to determine signs and magnitudes of Burgers vectors from terminating thickness contour lines. Higher deviation parameters s(g)--> are necessary, especially for dense dislocation arrangements.
- Language
-
- English
- Open access status
- green
- Identifiers
-
- DOI 10.1093/oxfordjournals.jmicro.a023793
- PMID 10791421
- Persistent URL
- https://sonar.ch/global/documents/46979
Statistics
Document views: 34
File downloads:
- Full-text: 0