Effect of tetragonality ratio on photo-induced domain switching in poled (Pb1-xLax)TiO3 ferroelectric ceramics

Abstract

The effect of the tetragonality (c/a) ratio on photo-induced domain switching in (Pb1-xLax)TiO3 ferroelectric ceramics preliminarily poled at 1.5kVmm(-1) was investigated by measuring photovoltaic current and acoustic emission (AE) signals. Results of total increment of photovoltaic current (J (pv)), total AE event count and AE energy distribution showed that non-steady state behavior of J (pv) was dominantly dependent on the activity of 90 degrees domain switching during illumination. The activity of photo-induced domain switching was explained in terms of the coercive field and the space charge field. It was confirmed that the magnitudes of the space charge field and coercive field were found to be optimal for the photo-induced 90 degrees domain switching at a c/a of 1.021. (C) 2000 Kluwer Academic Publishers.