Activation Layer Stabilization of High Polarization Photocathodes in Sub-Optimal RF Gun Environments

Mulhollan, Gregory ; /SLAC /Saxed Surface Science, Austin, TX

关键词: GALLIUM ARSENIDES;    CHEMICAL ACTIVATION;    PHOTOCATHODES;    POLARIZATION;    STABILIZATION;    CARBON DIOXIDE;    CORROSIVE EFFECTS;    CESIUM;    LITHIUM;    ENERGY GAP;    RF SYSTEMS;    ELECTRON GUNS;   

DOI  :  10.2172/992982
RP-ID  :  SLAC-PUB-14129
PID  :  OSTI ID: 992982
Others  :  TRN: US1008023

美国|英语

来源: SciTech Connect

【 摘 要 】

We have developed an activation procedure by which the reactivity to CO{sub 2}, a principal cause of yield decay for GaAs photocathodes, is greatly reduced. The use of a second alkali in the activation process is responsible for the increased immunity of the activated surface. The best immunity was obtained by using a combination of Cs and Li without any loss in near bandgap yield. Optimally activated photocathodes have nearly equal quantities of both alkalis.