Abrupt change in domain switching behavior within tetragonal phase regime of (x)Na1/2Bi1/2TiO3-(1 - X)K1/2Bi1/2TiO3

Abstract

We show that the lead-free piezoelectric system (x)Na1/2Bi1/2TiO3-(1 - x)K1/2Bi1/2TiO3 [xNBT-(1 - x)KBT] exhibits a boundary within its tetragonal phase regime at 0.58 < x < 0.60 across which the system exhibits an abrupt increase in reversible domain switching and high-field electrostrain for x > 0.58. We demonstrate that the abrupt changes, mimicking a composition-driven phase transition like scenario, are due to a sudden increase in the structural disorder for x > 0.58.