High Field Polarization Reversals in Liquid Electroded Barium Titanate Crystals

Abstract

The study of the polarization reversal in liquid electroded crystals of barium titanate has previously been mainly restricted to switching fields less than 1· 2 k V fcm. This paper studies the reversal in the field range 1· 5-6 kV fcm. For these higher fields, it is concluded, from switching current transients and " static" domain patterns, that the reversal is achieved by a small number of parallel. sided domains expanding radially sidewise at a constant velocity. All the domains appear to begin growing when the field is first applied. The cross-sectional shape of the domains varies from circular at fields greater than 3 kVfcm to square at fields less than 3 kVfcm. The number and distribution of the domain centres is determined by the surface conditions of the crystal, where the electrodes are situated, and not by the applied field.