Formation and evolution of charged domain walls in congruent lithium niobate

Abstract

We present experimental evidence of the formation of stable charged domain walls (CDWs) in congruent lithium niobate during switching. CDW evolution under the action of field pulses was in situ visualized. CDW boundary motion velocity is about 60 μm/s at 20 kV/mm. Relief of CDW strongly depends on applied field. Dielectric response in the presence of CDW demonstrates the pronounced frequency dependence in the range 50–150 °C. We propose the mechanism of CDW self-maintained propagation governed by self-consistent electrostatic interaction between the wall’s steps.

Fatigue of Lead Zirconate Titanate Ceramics II: Sesquipolar Loading

“…In the literature, several possible models for the explanation of fatigue under bipolar electric fields are given. Examples include domain wall pinning (or frozen domains) 17–19 where domains do not take part in the switching process any more, the formation of a dead layer underneath the electrodes 20 which influences for example the domain nucleation process, 21 or mechanical degradation of the sample 22 . The exact nature of the bipolar fatigue mechanism cannot be elucidated here, but the measured data indicates that for high values of | the sesquipolar fatigue behavior approaches that of bipolar fatigue, while for lower values of | it is closer to the unipolar case.…”

Bipolar Fatigue Caused by Field Screening in Pb(Zr,Ti)O3 Ceramics

“…[7][8][9][10] Several mechanisms of bipolar fatigue have been proposed in the literature. They include domain wall pinning (or frozen domains), [11][12][13] where domains do not take part in the switching process any more; the formation of a dead layer underneath the electrodes, 14 which influences for example the domain nucleation process 15 ; or mechanical degradation of the sample. 16 Despite all research efforts, a conclusion as to the exact nature of bipolar fatigue mechanisms in a bulk specimen has not yet been found.…”

Domain dynamics in stoichiometric lithium tantalate revealed by wet etching and on-line second harmonic generation

“…Thus, when the crystal is exposed to chemical etching during the stabilization phase, screening charges on the surface will be removed, and the chemical etching may assist the depolarization field causing domain-wall movement. 16 The domain wall will then aim to obtain a lowerenergy domain configuration with uncharged DWs.…”