Photocathode Performance Measurements for the SLC Polarized Electron Gun*
نویسندگان
چکیده
A low-voltage test system is used to qualify various III-V semiconductor materials as photocathodes for the SLC. The system features a load lock to introduce samples, high pumping speed, a sensitive residual gas -analyzer, and an infrared temperature detector. Heat cleaning, cesiation, and oxidation procedures have been studied to optimize cathode activation for achieving an optimum NEA surface. VGF GaAs, MBE-grown AlGaAs, MBE GaAs layered on AlGaAs, and MOCVD GaAsP cathodes with different active layer thicknesses and doping concentrations have been tested for quantum efficiency and lifetime. New higherpolarization strained-layer GaAs on GaAsP photocathodes have also been tested. Results and operational experience are discussed.
منابع مشابه
The Slc Polarized Electron Source
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