Position and momentum mapping of vibrations in graphene nanostructures

  title={Position and momentum mapping of vibrations in graphene nanostructures},
  author={Ryosuke Senga and Kazu Suenaga and Paolo Barone and Shigeyuki Morishita and Francesco Mauri and T. Pichler},
Propagating atomic vibrational waves—phonons—determine important thermal, mechanical, optoelectronic and transport characteristics of materials. Thus a knowledge of phonon dispersion (that is, the dependence of vibrational energy on momentum) is a key part of our understanding and optimization of a material’s behaviour. However, the phonon dispersion of a free-standing monolayer of a two-dimensional material such as graphene, and its local variations, have remained elusive for the past decade… 

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Vibrational STEM-EELS of Single Si Atom Point Defects in Graphene

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Three dimensional vectorial imaging of surface phonons.

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Breakdown of Optical Phonons' Splitting in Two-Dimensional Materials.

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