Transport, injection and storage of electric charges in alumina (Al/sub 2/O/sub 3/) single crystals

In this paper we describe the application of the pressure wave propagation method to the non-destructive measurement of the space charge dynamics in Al/sub 2/O/sub 3/ single crystals, under high voltage, at room temperature. A build up of a positive space charge in the vicinity of the anode is observed, and a mechanism is proposed to explain the origin of this charge.