Electron Emission by Nanosecond Switching in PLZT,

Copious electron emission from a PLZT ceramic surface takes place either when the surface is illuminated with laser pulses, or when short high-voltage pulses are applied. In the latter case, charge densities of up to 5 micron Ccm2 and current densities of some ten of amperes per square centimetre have been measured. Depending on the. position of the material in its phase diagram, different behaviour of the emission has been observed. Consequently the pulsed electron beam varies with respect to its pulse length, its amplitude, and its risetime. Further investigation of these data related to the corresponding material state might be a good diagnostic method, interesting for the switching dynamics in the ns-region. Moreover, a direct application as a pulsed Ferroelectric Electron Beam Source is envisaged, as the emission does, not rely on vacuum, but also works in low pressure gas or plasma. A maximum repetition frequency of 2 MHz has been established. An improvement of all data of the emitted electron beam seems feasible.