Depolarization of multidomain ferroelectric materials.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 31186422.
- Also identified by DOI 10.1038/s41467-019-10530-4 and PMC identifier 6560217.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Depolarization in ferroelectric materials has been studied since the 1970s, albeit quasi-statically. The dynamics are described by the empirical Merz law, which gives the polarization switching time as a function of electric field, normalized to the so-called activation field. The Merz law has been used for decades; its origin as domain-wall depinning has recently been corroborated by molecular dynamics simulations. Here we experimentally investigate domain-wall depinning by measuring the dynamics of depolarization. We find that the boundary between thermodynamically stable and depolarizing regimes can be described by a single constant, P<sub>r</sub>/ε<sub>0</sub>ε<sub>ferro</sub>E<sub>c</sub>. Among different multidomain ferroelectric materials the values of coercive field, E<sub>c</sub>, dielectric constant, ε<sub>ferro</sub>, and remanent polarization, P<sub>r</sub>, vary by orders of magnitude; the value for P<sub>r</sub>/ε<sub>0</sub>ε<sub>ferro</sub>E<sub>c</sub> however is comparable, about 15. Using this extracted universal value, we show that the depolarization field is similar to the activation field, which corresponds to the transition from creep to domain-wall flow.