Low-energy electron and low-energy positron holography

Surface atomic arrangement visualization via reference-atom-specific holography

We demonstrate the direct reconstruction of 3D atomic images from measured low-energy electron diffraction (LEED) intensity spectra. A multiple-incident angle and multiple-energy integral are first applied to the spectra to obtain a map of interatomic vectors. From this map, a nonbulk interatomic vector is chosen that points to a desired reference atom. A second integral transformation, using the chosen interatomic vector as a filter, is applied to the LEED spectra to produce images of individual atoms in the vicinity of the selected reference atom. This two-step method overcomes the problem of multiple, nonequivalent reference atoms and is applicable to elemental or compound materials.