Electric field induced phase transition and domain structure evolution in (Pb, La)(Zr, Sn, Ti)O₃ single crystal

Antiferroelectric (Pb, La)(Zr, Sn, Ti)O₃ (PLZST) single crystals with composition in the vicinity of morphotropic phase boundary have been grown and studied. From electric measurements, Raman study, and observation of domain structures, we found an electric field induced antiferroelectric to ferroelectric phase transition accompanied with fifteen times of strain difference. After this phase transition, the metastable ferroelectric phase (FE_in) is preserved with soften of A₁(TO₁) mode and increase of long-range force. Coexistence of tetragonal (T) and rhombohedral (R) domains has been observed in virgin sample. Electric field induced T to R phase transition is verified by both extinction angle and domain morphology changes. Clamping "polar" structure formed by the embedded R phase would contribute to increase of long-range force. The remarkable strain difference accompany with induced phase transition makes the PLZST single crystal a promising candidate for electric switch and actuator applications.