Effects of Grain Boundaries on Photovoltaic Current and Photoinduced Domain Switching in Ferroelectric Ceramics

Abstract

We investigated the effect of the grain size on the photovoltaic current in (PbLa)TiOceramics, and the photoinduced domain switching in (PbLa)TiOand BaTiOceramics. These behaviors in ferroelectric ceramics were attributed to the grain boundary at which photoexcited electrons were trapped. As the charged grain boundary acted as an electro-potential barrier which impeded the movement of electrons, the photovoltaic current showed a peak at a critical grain size. The space charge field built by the electrons trapped at the grain bound-aries was accounted for the photoinduced domain switching, and AE experimental results support well this account.