Study of Secondary Emission Enhanced Photoinjector

The secondary emission enhanced photoinjector (SEEP) is a very promising new approach to the generation of high-current, high-brightness electron beams. Primary electrons with a few thousand electron-volts of energy strike a specially prepared diamond window. The large Secondary Electron Yield (SEY) provides a multiplication of the number of electrons by about two orders of magnitude. The secondary electrons drift through the diamond under an electric field and emerge into the accelerating proper of the “gun” through a Negative Electron Affinity (NEA) surface of the diamond (Hydrogen terminated). We present the calculation of heating power sources and the temperature distribution in detail. Some properties of the secondary electron beam related to beam dynamics are also reported. The results demonstrate the feasibility of this kind of cathode.