Ferroelectric sources and their application to pulsed power: a review

We present in this review an account of recent research into the use of ferroelectrics as electron beam sources for pulsed power applications. The work is reviewed according to the ferroelectric material used and the switching process employed. Most of the current research uses PLZT or PZT, which can be ferroelectric, antiferroelectric, or paraelectric depending on the stoichiometry. Switching is accomplished by the application of a fast-rising electric field to the ferroelectric material. The most commonly used materials are PLZT 2/95/5 and PLZT 8/65/35 or PZT (with no lanthanum): in the former case, the applied field switches the material from the antiferroelectric state to the ferroelectric state, and in the latter cases, around a hysteresis loop. Results have been reported with ferroelectric cathodes where current densities of up to a few hundred amperes per square centimeter have been achieved, with pulse durations of several microseconds. With shorter duration pulses and PLZT cathodes, repetition rates of up to 2 MHz have been achieved. In this paper, we focus on the results reported in the literature, and include a brief account of the physical interpretation of the data. The possible use of ferroelectric sources for pulsed power applications is indicated.