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The 1s-State Analysis Applied to High-Angle, Annular Dark-Field Image Interpretation—When Can We Use It?

Published online by Cambridge University Press:  22 January 2004

Geoffrey R. Anstis
Geoffrey R. Anstis
Affiliation:
Department of Applied Physics, University of Technology, Sydney, P.O. Box 123, Broadway, NSW 2007, Australia
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Abstract

A small probe centered on an atomic column excites the bound and unbound states of the two-dimensional projected potential of the column. It has been argued that, even when several states are excited, only the 1s state is sufficiently localized to contribute a signal to the high-angle detector. This article shows that non-1s states do make a significant contribution for certain incident probe profiles. The contribution of the 1s state to the thermal diffuse scattering is calculated directly. Sub-Ångstrom probes formed by Cs-corrected lenses excite predominantly the 1s state and contributions from other states are not very large. For probes of lower resolution when non-1s states are important, the integrated electron intensity at the column provides a better estimate of image intensity.

Keywords

high-resolution electron microscopyscanning transmission electron microscopyhigh-angle annular dark-field imaging1s statethermal diffuse scatteringmultislice methodfrozen phonon
Type
Research Article
Information
Microscopy and Microanalysis , Volume 10 , Issue 1 , February 2004 , pp. 4 - 8
Copyright
© 2004 Microscopy Society of America

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References

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