The effect of thermal history on the ferroelectric domain pattern and the dynamics in β-las single crystals

Abstract

Investigation of ferroelectric domain structure in β-LAS single crystals showed strong influence of sample's thermal history on it's pattern. The only orientation of domain walls for β-LAS samples “as grown” and after ferroelastic-ferroelectric phase transition is crystallographic direction [100]. Following paraelectric-ferroelectric phase transition two other orientations of domain walls appear: [302] and [30]. It was observed that above mentioned directions correspond to two orientations of “domain texture” found in very narrow temperature range ΔT ∼ 1 deg below Curie temperature (T_c = 462 K). Switching process in β-LAS single crystals in (ac) plane spreads along direction [100] irrespective of ferroelectric domain structure pattern.