Crystallographic dependence of loss in domain engineered relaxor-PT single crystals

Domain engineered < 001 > oriented relaxor-PbTiO3 ferroelectric crystals exhibit high electromechanical properties and low mechanical Q values, analogous to soft piezoelectric ceramics. However, their characteristic low dielectric loss (<= 0.5%) and strain-electric field hysteresis are reflective of hard piezoelectric materials. In this work, the electromechanical behavior of relaxor-PT crystals was investigated as a function of crystallographic orientations. It was found that the electrical and mechanical losses in crystals depends on the specific engineered domain configuration, with high Q observed for the < 110 > orientation. The high Q, together with high electromechanical coupling (similar to 0.9) for < 110 > oriented relaxor-PT crystals, make them promising candidates for resonant based high power transducer applications.