nl6b00524_si_001.pdf (1.91 MB)
Direct Atom Imaging by Chemical-Sensitive Holography
journal contribution
posted on 2016-04-12, 00:00 authored by Tobias Lühr, Aimo Winkelmann, Gert Nolze, Dominique Krull, Carsten WestphalIn
order to understand the physical and chemical properties of
advanced materials, functional molecular adsorbates, and protein structures,
a detailed knowledge of the atomic arrangement is essential. Up to
now, if subsurface structures are under investigation, only indirect
methods revealed reliable results of the atoms’ spatial arrangement.
An alternative and direct method is three-dimensional imaging by means
of holography. Holography was in fact proposed for electron waves,
because of the electrons’ short wavelength at easily accessible
energies. Further, electron waves are ideal structure probes on an
atomic length scale, because electrons have a high scattering probability
even for light elements. However, holographic reconstructions of electron
diffraction patterns have in the past contained severe image artifacts
and were limited to at most a few tens of atoms. Here, we present
a general reconstruction algorithm that leads to high-quality atomic
images showing thousands of atoms. Additionally, we show that different
elements can be identified by electron holography for the example
of FeS2.