Defect-dipole alignment and strain memory effect in poled Li doped (Bi_0.5Na_0.4K_0.1)_0.98Ce_0.02TiO₃ ceramics

Asymmetric ferroelectric hysteresis (P–E) loops and strain hysteresis (S–E) curves are detected in poled-aged Li doped (Bi_0.5Na_0.4K_0.1)_0.98Ce_0.02TiO₃ ceramics at room temperature. Temperature dependence of electrical and structural analysis is used to study the stability of electrically induced long-range ferroelectric order. Interestingly, this asymmetric characteristic can sustain at 80 °C ≤ T ≤ 90 °C, where the ferroelectric and non-ergodic relaxor phase coexist. Our results suggest that the preferentially reoriented defect dipoles have the pinning effect on temperature- and electric field- induced phase transition between long-range ferroelectric and relaxor.