Optimization of k-space sampling in atomic imaging by electron emission holography

P. M. Len, S. Thevuthasan, A. P. Kaduwela, M. A. Van Hove, C. S. Fadley

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Two limiting-case algorithms have previously been proposed for holographically imaging atoms near surfaces using photoelectron diffraction data and other diffraction data associated with electron emission: (i) a phased sum of Fourier transforms of scanned-angle data taken at several energies from Barton, (ii) and a phased sum of Fourier transforms of scanned-energy data taken along several directions due to Tong et al. We first point out that both methods are equivalent three-dimensional transforms in the wave vector k of the emitted electron, differing only in the way they sample k-space. A continuum of different sampling densities in the direction and magnitude of k exists in such holography, spanning the two limits previously discussed. An additional variant on these methods involves using only a small cone of data in k-space for each transform. Using model diffraction calculations for localized electron emission (e.g., core photoelectron emission) from Cu(001) clusters, we have explored the full range of k-space sampling possible, and find that optimum image quality is expected for choices intermediate between the extreme limits of scanned-angle or scanned-energy. General rules for optimizing image quality for a given data-set range are also discussed, and used to evaluate the sampling choices made in some prior experimental studies.

Original languageEnglish
Pages (from-to)535-546
Number of pages12
JournalSurface Science
Volume365
Issue number2
DOIs
Publication statusPublished - 20 Sep 1996
Externally publishedYes

Fingerprint

Electron emission
Holography
holography
electron emission
Diffraction
sampling
Sampling
Photoelectrons
Imaging techniques
Image quality
optimization
Fourier transforms
photoelectrons
diffraction
energy
Cones
cones
continuums
Atoms
Electrons

Keywords

  • Angle resolved photoemission
  • Copper
  • Electron-solid interactions, scattering, diffraction
  • Photoelectron diffraction
  • Photoelectron holography
  • Semi-empirical models and model calculations
  • Single crystal surfaces

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Condensed Matter Physics
  • Surfaces and Interfaces

Cite this

Len, P. M., Thevuthasan, S., Kaduwela, A. P., Van Hove, M. A., & Fadley, C. S. (1996). Optimization of k-space sampling in atomic imaging by electron emission holography. Surface Science, 365(2), 535-546. https://doi.org/10.1016/0039-6028(96)00719-4

Optimization of k-space sampling in atomic imaging by electron emission holography. / Len, P. M.; Thevuthasan, S.; Kaduwela, A. P.; Van Hove, M. A.; Fadley, C. S.

In: Surface Science, Vol. 365, No. 2, 20.09.1996, p. 535-546.

Research output: Contribution to journalArticle

Len, PM, Thevuthasan, S, Kaduwela, AP, Van Hove, MA & Fadley, CS 1996, 'Optimization of k-space sampling in atomic imaging by electron emission holography', Surface Science, vol. 365, no. 2, pp. 535-546. https://doi.org/10.1016/0039-6028(96)00719-4
Len, P. M. ; Thevuthasan, S. ; Kaduwela, A. P. ; Van Hove, M. A. ; Fadley, C. S. / Optimization of k-space sampling in atomic imaging by electron emission holography. In: Surface Science. 1996 ; Vol. 365, No. 2. pp. 535-546.
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