LASA Cs2Te Photocathodes: The Electron Source for XFELs

  • Carlo PaganiEmail author
  • Paolo Michelato
  • Laura Monaco
  • Daniele Sertore
Conference paper


Laser triggered photocathodes are key components of the electron sources for the XFELs. Research on semiconductor photocathodes started in the 90s at INFN LASA Milano by studying multialkali antimonied compounds (Cs3Sb, K3Sb, and K2CsSb), showing that the high QE was coupled with very high sensitivity to vacuum pollution. To avoid these deterioration issues, we focused our activity on Cs2Te which, while sensitive to UV light, has better resistance to gas contamination. Since then, we have a dedicated R&D program aimed at developing a always more reliable photocathode and its associated transport systems. Today our photocathodes are used at FLASH and at European XFEL at DESY Hamburg, PITZ at DESY Zeuthen, APEX in LBNL, FAST at FNAL and at LCLS-II at SLAC.


Photocathodes Electron sources Free electron laser 


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Copyright information

© Springer Nature Switzerland AG 2018

Authors and Affiliations

  • Carlo Pagani
    • 1
    • 2
    Email author
  • Paolo Michelato
    • 2
  • Laura Monaco
    • 2
  • Daniele Sertore
    • 2
  1. 1.Dipartimento di Fisica “Aldo Pontremoli”Universitá degli Studi di MilanoMilanoItaly
  2. 2.INFN - LASASegrate (Milano)Italy

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