Electron beam production for microwave generation using a ferroelectric cathode

Data is presented on the production of electron beams from a ferroelectric cathode at voltages of order 0.5 MV and current densities of order 100 A/cm/sup 2/ In comparison with data at lower voltages the beam current scales as three halves power of the voltage. An interpretation of this scaling, based on the coupling of electrostatic energy from the ferroelectric to the gun is presented.