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arXiv · 1705.09709

Improving the Functional Control of Aged Ferroelectrics using Insights from Atomistic Modelling

J. B. J. Chapman·R. E. Cohen·A. V. Kimmel·D. M. Duffy
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Abstract

We provide a fundamental insight into the microscopic mechanisms of the ageing processes. Using large scale molecular dynamics simulations of the prototypical ferroelectric material PbTiO3, we demonstrate that the experimentally observed ageing phenomena can be reproduced from intrinsic interactions of defect-dipoles related to dopant-vacancy associates, even in the absence of extrinsic effects. We show that variation of the dopant concentration modifies the material's hysteretic response. We identify a universal method to reduce loss and tune the electromechanical properties of inexpensive ceramics for efficient technologies.

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J. B. J. Chapman, R. E. Cohen, A. V. Kimmel, D. M. Duffy. 2017-05-26. Improving the Functional Control of Aged Ferroelectrics using Insights from Atomistic Modelling. https://doi.org/10.1103/physrevlett.119.177602

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