Enhanced piezoelectric properties of potassium niobate single crystals with fine engineered domain configurations

Potassium niobate (KNbO3) single crystals were grown by a top seed solution growth (TSSG) method. At first, the electric field was applied along [0 0 1]c (cubic notification system) direction of KNbO3 crystals to induce the engineered domain configurations into KNbO3 crystals. Prior to domain engineering, the piezoelectric properties of [0 0 1]c oriented KNbO3 single-domain crystals were measured. These measured values were completely consistent with the calculated apparent d31 and d32. Finally, the engineered domain configurations were induced into KNbO3 crystals. As a result, piezoelectric properties increased with decreasing domain sizes of the engineered domain configuration.