High-quality ferroelectric Bi0.5K0.5TiO3‒BiFeO3 solid-solution single crystals grown under high-pressure oxygen atmosphere

Abstract Ferroelectric (Bi 0.5 K 0.5 )TiO 3 –BiFeO 3 solid solutions are promising materials for high-temperature piezoelectric applications because of their high depolarization temperature. In this study, we demonstrate the successful growth of high-quality (Bi 0.5 K 0.5 )TiO 3 –BiFeO 3 single crystals near the morphotropic phase boundary by a flux method. Crystal growth at a high oxygen pressure of 0.9 MPa drastically reduces leakage currents, which enables ferroelectric polarization switching and a piezoelectric response associated with a rotation of polar nanosized domains. This study contributes to further detailed analyses of the relationship between crystal structures and ferroelectric properties of the (Bi 0.5 K 0.5 )TiO 3 –BiFeO 3 solid-solution system.