Enhanced piezoelectric activity and temperature stability of [111]-oriented orthorhombic 0.68Pb(Mg1/3Nb2/3) O3-0.32PbTiO3 single crystals by domain size engineering

The dielectric and piezoelectric properties of [1 1 1]-oriented orthorhombic Pb(Mg1/3Nb2/3)O-3-PbTiO3 (PMN-PT) single crystals (3O multi-domain state) with various domain sizes were investigated by poling control. The free dielectric permittivity (epsilon(T)(33)/epsilon(0)) and longitudinal piezoelectric coefficient (d(33)) were 6400 and 900 pC N-1, respectively, for samples with domain sizes of similar to 2 mu m, nearly twice that of similar to 20 mu m. Together with good temperature stability (Delta d(33)/d(33(25 degrees C)) <8%) up to the orthorhombic tetragonal phase transition temperature, the 3O PMN PT crystals with fine domain structures are promising candidate for sensors and transducers. (C) 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.