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arXiv · 1004.4652

Finite-Temperature Atomic Structure of 180^o Ferroelectric Domain Walls in PbTiO3

Arzhang Angoshtari·Arash Yavari
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Abstract

In this letter we obtain the finite-temperature structure of 180^o domain walls in PbTiO3 using a quasi-harmonic lattice dynamics approach. We obtain the temperature dependence of the atomic structure of domain walls from 0K up to room temperature. We also show that both Pb-centered and Ti-centered 180^o domain walls are thicker at room temperature; domain wall thickness at T=300K is about three times larger than that of T=0K. Our calculations show that Ti-centered domain walls have a lower free energy than Pb-centered domain walls and hence are more likely to be seen at finite temperatures.

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Arzhang Angoshtari, Arash Yavari. 2010-04-26. Finite-Temperature Atomic Structure of 180^o Ferroelectric Domain Walls in PbTiO3. https://doi.org/10.1209/0295-5075%2F90%2F27007

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