Structural and electrical characterization of ferroelectric SrBi ₂Nb₂O₉ single crystals grown by high-temperature self-flux solution

High-quality SrBi₂Nb₂O₉ (SBN) single crystals were grown from a melt using a high-temperature self-flux solution method and Bi₂O₃ added with B₂O₃ as a flux. A suitable thermal profile involving slow cooling rates allowed growing large and translucent SBN crystals exhibiting platelet morphology with typical size ∼5 × 5 mm² and thickness approximately 400 μm. X-ray diffraction revealed a dominant (001)-orientation of the major face of the platelet crystals and edges oriented parallel to the [110] directions. The dielectric properties were evaluated along the ab-plane and in the c-axis direction. The ferro-paraelectric phase transition was observed at T_C = 440°C with Curie-Weiss relationship above T_C. The anisotropy of dielectric permittivity, i.e., the ratio between permittivity in the ab-plane and along c-axis was about 10 at T_C-The obtained results are used to discuss the observed correlations between anisotropy, crystalline orientation, and electrical properties.