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arXiv · 1905.07191

Origin of sawtooth domain walls in ferroelectrics

J. Zhang·Y. -J. Wang·J. Liu·J. Xu·D. Wang·L. Wang·X. -L. Ma·C. -L. Jia·L. Bellaiche
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Abstract

Domains and domain walls are among the key factors that determine the performance of ferroelectric materials. In recent years, a unique type of domain walls, i.e., the sawtooth-shaped domain walls, has been observed in BiFeO$_{3}$ and PbTiO$_{3}$. Here, we build a minimal model to reveal the origin of these sawtooth-shaped domain walls. Incorporating this model into Monte-Carlo simulations shows that (i) the competition between the long-range Coulomb interaction (due to bound charges) and short-range interaction (due to opposite dipoles) is responsible for the formation of these peculiar domain walls and (ii) their relative strength is critical in determining the periodicity of these sawtooth-shaped domain walls. Necessary conditions to form such domain walls are also discussed.

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J. Zhang, Y. -J. Wang, J. Liu, J. Xu, D. Wang, L. Wang, X. -L. Ma, C. -L. Jia, L. Bellaiche. 2019-05-17. Origin of sawtooth domain walls in ferroelectrics. https://doi.org/10.1103/physrevb.101.060103

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