Ferroelectric SrBi₂Ta₂O₉ single-crystal growth and characterization

Using a new composite flux and an improved growth process, large and high-quality ferroelectric SrBi₂Ta₂O₉ (SBT) single crystals (up to 25 × 20 mm² area) were successfully grown from high-temperature solutions. The effects of chemical, thermodynamic, and kinetic parameters on the growth results were systematically studied. The optimum system for the growth of SBT crystals has been identified. B₂O₃ additive was shown to play an important role in improving the effectiveness of the Bi₂O₃ solvent. The grown SBT single crystals exhibit a dominant (001)-orientation and large single-domain areas. The dielectric and ferroelectric properties measured in relation to crystal orientations have confirmed the absence of any polarization component normal to the (Bi₂O₂)²⁺ sheets of the structure, indicating a high anisotropy in the properties.