Electron Emission from Ferroelectric Cathodes Stimulated by Repetition Frequency High-Voltage Pulse

Stable electron emission from ferroelectric cathodes made of lead zirconate-titanate Lanthanum doped (PLZT) ferroelectric ceramic stimulated by high-voltage pulses with a repetition rate of 80 Hz is obtained. The emission properties and lifetime are studied. To excite electron emission and obtain bigger current, a positive driving pulse is applied to the rear electrode of the cathodes, and an extracting voltage is applied to the graphite anode. The image and the structure of the emitting surface and broken side of the samples tested for electron emission before and after are studied by photographs and scanning electron microscopy. It is found that a substantial damage presenting in the tested cathodes. According to the experimental results, some possible interpretations are given for the damage of PLZT samples.