Electron emission from ferroelectric ceramics with a special design patterned front electrode

Electron emission from a ceramic disk is due to spontaneous polarization sw itching induced by a high-voltage pulse applied to the surface electrodes. With a conventional front electrode, emission was erratic as a function of samples and decayed with shot number. On the contrary, when the front elect rode consisted of a pattern of unconnected patches contained within a ring, emission was stable. The physics of the two configurations is investigated and a possible interpretation of the two different behaviors is given. (C) 1999 American Institute of Physics. [S0021-8979(99)05512-7].