Crystal Growth and Characterization of (Bi<sub>0.5</sub>Na<sub>0.5</sub>)TiO<sub>3</sub>-BaTiO<sub>3</sub> Single Crystals Obtained by the Top-Seeded Solution Growth Method under High-Pressure Oxygen Atmosphere

Abstract

A single crystal of ferroelectric 0.88(Bi,Na)TiO30.12BaTiO3 (BNTBT) solid solution with tetragonal P4mm structure was grown by the top-seeded solution growth (TSSG) method at a high oxygen pressure (PO2) of 0.9 MPa. The crystals grown by the high-PO2 TSSG method exhibited a large remanent polarization (Pr) of 54 μC/cm2, which leads to a spontaneous polarization of 54 μC/cm2. The large Pr compared with that of crystals grown at PO2 = 0.1 MPa is suggested to originate from a low oxygen vacancy concentration for the crystals grown at a higher PO2. The high-PO2 TSSG method was demonstrated to be effective for obtaining BNTBT crystals with superior polarization and piezoelectric properties.