title: Single atom image contrast: conventional dark-field and bright-field electron microscopy.
abstract: Single atom inage intensities are calculated for bright-field and various dark-field modes, including the ideal beam stop, a wire beam stop, tilted illumination and a displaced aperture. Comparisons of scattering amplitudes and elastic scattering cross-sections are made with different object potentials and scattering formulations. The image contrast for one mercury atom (Z equals 80) on a column of carbon atoms (Z equals 6) as the substrate is also discussed for both the bright-field and the various dark-field situations.
mesh_terms: D002244:Carbon; D003624:Darkness; D007089:Image Enhancement; D008027:Light; D008029:Lighting; D013058:Mass Spectrometry; D008628:Mercury; D008854:Microscopy, Electron; D008858:Microscopy, Phase-Contrast; D008962:Models, Theoretical; D055095:Optics and Photonics
chemical_list: D002244:Carbon; D008628:Mercury