First Operation of an Ungated Diamond Field-Emission Array Cathode in a L-Band Radiofrequency Electron Source

摘要

We report on the first successful operation of a field-emitter-array cathodein a conventional L-band radio-frequency electron source. The cathode consistedof an array of $\sim 10^6$ diamond diamond tips on pyramids. Maximum current onthe order of 15~mA were reached and the cathode did not show appreciable signsof fatigue after weeks of operation. The measured Fowler-Nordheimcharacteristics, transverse beam density, and current stability are discussed.Numerical simulations of the beam dynamics are also presented.