Electrical De-poling and Re-poling of Relaxor-PbTiO3 Piezoelectric Single Crystals without Heat Treatment

Abstract

Re-poling of unexpected partially depoled piezoelectric materials conventionally need to be first fully depoled through annealing above their Curie temperature (Tc) to revive piezoelectric performances. Here, we investigated de-poling and re-poling of Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 (PIN-PMN-PT) single crystals under electric fields at room temperature. We found that alternating current (AC) electric fields with amplitudes near the coercive field (Ec) at low frequencies (< 10 Hz) can be employed to successfully depolarize poled crystals at room temperature. We also demonstrated a reversible polarization switching process with a relaxor-PT single crystal ultrasound transducer without device performance degradation. This experimental observation is supported by phase-field simulation, showing that AC electric fields can readily induce de-poling at room temperature, while DC electric fields induce a transient depoled state only within an uncontrollable short period of time. The findings suggested new strategies for unprecedented in-device tailoring of the polarization states of ferroelectric materials.