摘要
铁电阴极因其优异的电子发射性能在高功率微波管的电子束源、平板显示技术以及宇航推进器等领域有着广阔应用前景而日益受到人们的重视.大量研究表明,铁电阴极电子发射性能受阴极材料性能的影响.在激励电场作用下,铁电阴极材料会产生表面非屏蔽电荷而引起极化强度的变化,这表明铁电阴极电子发射性能可能与阴极材料的极化强度变化量存在着某种关系.为研究阴极材料极化强度变化量对铁电阴极电子发射性能的影响,以掺镧锆锡钛酸铅铁电和反铁电陶瓷样品作为阴极材料,通过正半周电滞回线测试得到阴极材料在不同电场强度下的极化强度变化量,测量得到电子发射电流强度随激励电场的变化曲线,并分析了电子发射电流强度与极化强度变化量的关系.结果表明,两种样品电子发射电流强度与极化强度变化量正相关.
Ferroelectric cathodes exhibit huge potentials in high-power microwave tube electron beam source, panel display, and the propeller space navigation, due to their superior properties. The material properties of the ferroelectric cathode have been proved to have a significant influence on electron emission, which is indicated in recent research work. In the course of electron emission, the variation of polarization can be caused by non-shielded surface charge which is induced by high trigger voltage. A certain relationship may be found between polarization variation and current intensity of electron emission. To study the relationship between current intensity of electron emission and polarization variation in ferroelectric cathodes, the samples of lanthanum-doped lead zirconate stannate titanate ferroelectric and antiferroelectric ceramics are prepared by the method of solid state calcinations, and the polarization variations of the material under different voltages are measured in the positive half cycle test of hysteresis loop. The curve of the electron emission current intensity versus the trigger voltage is measured, and then the relationship between electron emission current intensity and polarization variation is investigated. The results show that the electron emission current intensities of the two samples are both directly proportional to the polarization variation.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2012年第8期426-431,共6页
Acta Physica Sinica
基金
国家自然科学基金(批准号:10875095)
国家重点基础研究发展计划(批准号:2009CB623306)资助的课题~~
关键词
反铁电陶瓷
极化
铁电阴极电子发射
antiferroelectric ceramics, polarization, ferroelectric cathode electron emission
