Explosive electron emission from a ferroelectric surface initiated in triple junctions

This paper presents the results of a study of the electron emission from the surface of a ferroelectric (barium titanate or titanium dioxide) in vacuum. It has been shown experimentally that the electron beam source is the plasma generated by the explosion of the metal electrode and ferroelectric at the site of their contact - a triple junction. Explosive electron emission at comparatively low voltages occurs due to the electric field at a triple junction which is high enough to initiate field emission. This field arises because of the small electrode radius resulting in inhomogeneous geometry at the contact and because of the substantially different permittivities of the three media: metal, ferroelectric, and vacuum. The plasma origin of this discharge is unambiguously indicated by the electron and ion emission characteristics.