Vibrational spectroscopy at atomic resolution with electron impact scattering

@article{Venkatraman2019VibrationalSA,
  title={Vibrational spectroscopy at atomic resolution with electron impact scattering},
  author={Kartik Venkatraman and Barnaby D.A. Levin and Katia March and Peter Rez and Peter A. Crozier},
  journal={Nature Physics},
  year={2019},
  pages={1-5}
}
Atomic vibrations control all thermally activated processes in materials, including diffusion, heat transport, phase transformations and surface chemistry. Recent developments in scanning transmission electron microscopy (STEM) have enabled nanoscale probing of vibrational modes using electron energy-loss spectroscopy (EELS)1,2. Although atomically resolved analysis is routine in STEM, vibrational spectroscopy employing oscillating dipoles yields signals originating from regions tens of… 
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49 Citations

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TLDR
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TLDR
In crystals, long- and short-wavelength phonon modes can be probed simultaneously with on-axis vibrational STEM EELS to help develop a fundamental connection between vibrational excitations and bonding arrangements at atomic-scale heterogeneities in materials.
Atomic Resolution Vibrational EELS Acquired from an Annular Aperture
Recently, sub-10 meV resolution of electron energy loss spectroscopy (EELS) in scanning transmission electron microscopy (STEM) [1] makes the detection of vibrational modes at atomic scale possible.…
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It was recently shown that phonon spectral mapping of atomic structure is possible in scanning transmission electron microscopy. These results were obtained by deflecting the transmitted beam to…
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TLDR
A novel method to use a so-called δ thermostat in the classical molecular dynamics simulation to generate frequency dependent configurations of the vibrating specimen's atomic structure and provides vibrational spectrum images at a cost comparable to standard frozen phonon calculations is introduced.
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