First-principles many-body study of the electronic and optical properties of CsK2Sb, a semiconducting material for ultra-bright electron sources.

  title={First-principles many-body study of the electronic and optical properties of CsK2Sb, a semiconducting material for ultra-bright electron sources.},
  author={Caterina Cocchi and S. Mistry and Martin Anton Helmut Schmeisser and J. K{\"u}hn and Thorsten Kamps},
  journal={Journal of physics. Condensed matter : an Institute of Physics journal},
  volume={31 1},
  • C. Cocchi, S. Mistry, +2 authors T. Kamps
  • Published 1 September 2018
  • Medicine, Materials Science, Physics
  • Journal of physics. Condensed matter : an Institute of Physics journal
We present a comprehensive first-principles investigation of the electronic and optical properties of CsK2Sb, a semiconducting material for ultra-bright electron sources for particle accelerators. Our study, based on density-functional theory and many-body perturbation theory, provides all the ingredients to model the emission of this material as a photocathode, including band gap, band dispersion, and optical absorption. An accurate description of these properties beyond the mean-field picture… 

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