Department High Brightness Beams
Photoemission Sources for Electron Accelerators - Photocathodes
The beam quality of a SRF photoinjector in terms of brightness and current is ultimately given by the electron source itself. In an SRF photoinjector electrons are generated by illuminating a photocathode with light pulses from a drive laser. This photocathode must be embedded into the SRF cavity, such that the electrons can be quickly accelerated to mitigate space charge effects. The focus of the activities is to understand correlations between cathode material, preparation, treatment and electron beam parameters such as transverse emittance, which is linked to the brightness of the beam generated with the SRF photoinjector. Our goal is to provide high quantum efficiency bialkali antimonide photocathodes for the operation of the SRF-photoinjector and beyond that to understand fatigue effects and fundamental electronic and optical properties in collaboration with Prof. C. Cocchi from U Oldenburg.
The photocathode laboratory
The photocathode laboratory of the Department High Brightness Beams
The MTE laboratory
The MTE laboratory
PhoTEx: Photoemission and Transverse Energy Experiment
Publications
- J. Dube et al., Triple Evaporation of Bialkali Antimonide Photocathodes and Photoemission Characterization at the PhoTEx Experiment (2025). Arxiv
- C. Cocchi et al., Electronic structure and core electron fingerprints of caesium-based multi-alkali antimonides for ultra-bright electron sources, Scientific Reports, 9, 18276, (2019). SR
- M. A. H. Schmeißer et al., Towards the operation of Cs-K-Sb photocathodes in superconducting rf photoinjectors, Phys. Rev. Accel. Beams 21, 113401, (2018). PRAB
- C. Cocchi et al., First-principles many-body study of the electronic and optical properties of CsK2Sb, a semiconducting material for ultra-bright electron sources, J. Phys.: Condens. Matter, 31, 014002, (2018). JPCM