PPPS-2013: Controlled Porosity Reservoir cathodes and photocathodes

摘要

Controlled Porosity Reservoir (CPR) cathodes offer high current density operation with long life and superior emission uniformity [1]. Calabazas Creek Research, Inc. (CCR) recently delivered a 100 KW, X-Band, multiple beam klystron (MBK) with fifteen CPR cathodes operating at 30 A/cm2 and is currently fabricating a magnetron injection gun and an annular beam klystron (ABK) using the cathodes. The high current density capability eliminated beam compression for the MBK and ABK, dramatically simplifying the design. CCR, in collaboration with the University of Maryland, implemented CPR technology into cesiated tungsten photocathodes. Photocathode tests demonstrated superior performance over previous designs with an increase in lifetime exceeding two orders of magnitude. Research improved theoretical modeling of Knudsen Flow and barium evaporation, leading to an advanced computational tool for designing CPR cathodes.