Effects of growth conditions on the domain structure and dielectric properties of (1 − x)Pb(Sc1/2Nb1/2)O3–xPbTiO3 single crystals

The studies of the (1 − x)Pb(Sc1/2Nb1/2)O3–xPbTiO3 (PSN–PT) single crystals reveal that the chemical and physical properties of the materials are affected by the growth conditions. By the measurements of the dielectric constant as a function of temperature upon cooling, it is found that crystals grown from the same charged stoichiometric composition (x = 0.425), but under different flux environments (i.e. the composition of flux and the flux to PSN–PT ratios are varied), show anomalies (i.e. phase transitions) at different temperatures. This phenomenon is attributed to the complex local chemical structure of the PSN–PT solid solution single crystals with B-site random occupancy of three different cations (Sc3+, Nb5+ and Ti4+). The dielectric and domain structure of the PSN–PT crystals with composition near the morphotropic phase boundary (MPB) are investigated, showing much more complex situations compared with Pb(Sc1/2Nb1/2)O3.