Genetic Algorithm Structure Search for Cs-Sb photocathode on a SiC(100) substrate

ORAL

Abstract

Electron beams are an essential component in the development of a deeper understanding of quantum matter. The beam's spatial and temporal resolution depends directly on its brightness, which is controlled by the photocathode material. Binary compounds found in the Cs-Sb family grown on a SiC substrate have been identified as a potential photocathode material that can improve beam brightness. In this study, we utilize two methods to identify the structures and properties of energetically stable thin films of Cs-Sb grown on SiC(100) and utilize density functional theory to predict their photoemission properties. The first method employs a genetic algorithm structure to search over a range of chemical potentials and partial pressures. For the second method, thin films are generated by cleaving the stable bulk phases of Cs-Sb and placing the cleaved surface onto the SiC substrate via a lattice matching algorithm. We aim to identify suitable synthesis conditions for optimal photocathode properties. All data produced in this study will be available on our open-source database MaterialsWeb.org.

*This work was supported by the U.S. National Science Foundation under Award PHY-1549132, the Center for Bright Beams.

Presenters

  • Jason Gibson

    • University of Florida

Authors

  • Jason Gibson

    • University of Florida
  • Joshua Paul

    • University of Florida
  • Alice Galdi

    • Cornell
  • Richard Hennig

    • University of Florida
    • Department of Materials Science and Engineering, University of Florida
    • Materials Science and Engineering, University of Florida