Significant performance enhancement of Nd-doped Pb(In0.5Nb0.5)O3–PbTiO3 ferroelectric crystals.

High-performance piezoelectric materials for actuators, sensors, and transducers are urgently required. It would be ideal to always have high piezoelectric performance and high ferroelectric-ferroelectric phase transition temperature, but we have only one in most cases. Pb(In_0.5Nb_0.5)O₃–PbTiO₃ (PIN-PT) crystals have a high rhombohedral-tetragonal phase transition temperature (T_RT), but the piezoelectric performance is not very satisfactory. Here, Nd-doped PIN-0.33PT single crystals were grown, where the enhanced piezoelectric d₃₃ and electromechanical coupling coefficient k₃₃ are 2100 pC/N and 91%, which are 80% and 5.8% higher than those for virgin PIN-0.33PT single crystals (1160 pC/N and 86%) and are superior to that of other compositions of PIN-PT crystals. Piezo-response force microscopy was adopted to study the domain structure, and the domain size was found to decrease after Nd doping, which contributes to the enhanced piezoelectric performance. This study offers a good paradigm for enhancing the piezoelectric performance of high Curie temperature ferroelectric single crystals. [ABSTRACT FROM AUTHOR]