Operation of ferroelectric cathodes with control grid

Results of experimental study of high-current electron beam generation in a planar diode with a ferroelectric plasma cathode and a control grid are presented. The plasma is formed as a result of noncomplete discharge on the surface of a BaTiO/sub 3/ sample when a driving pulse is applied to its rear electrode. This noncomplete surface discharge leads also to the appearance of fast plasma flows which fill the anode-cathode gap prior to the application of the accelerating electric field. The measured plasma densities and flow velocities allow to estimate the bias potential of the control grid which is required for the suppression of the plasma flows. The dependence of the plasma density on the grid potential is presented. Using the control grid, operation of the diode with the ferroelectric plasma cathode is achieved with negligible plasma prefilling of the anode-cathode gap.