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

Ferroelectric (Bi0.5K0.5)TiO3-BiFeO3 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 (Bi0.5K0.5)TiO3-BiFeO3 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 (Bi0.5K0.5)TiO3-BiFeO3 solid-solution system. (C) 2022 The Author(s). Published on behalf of The Japan Society of Applied Physics by IOP Publishing Ltd