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arXiv · 1909.02536

Uncompensated Polarization in Incommensurate Modulations of Perovskite Antiferroelectrics

Tao Ma·Zhongming Fan·Bin Xu·Tae-Hoon Kim·Ping Lu·Laurent Bellaiche·Matthew J. Kramer·Xiaoli Tan·Lin Zhou
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Abstract

Complex polar structures of incommensurate modulations (ICMs) are revealed in chemically modified PbZrO$_3$ perovskite antiferroelectrics using advanced transmission electron microscopy techniques. The Pb-cation displacements, previously assumed to arrange in a fully-compensated antiparallel fashion, are found to be either antiparallel but with different magnitudes, or in a nearly orthogonal arrangement in adjacent stripes in the ICMs. Ab initio calculations corroborate the low-energy state of these arrangements. Our discovery corrects the atomic understanding of ICMs in PbZrO$_3$-based perovskite antiferroelectrics.

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Tao Ma, Zhongming Fan, Bin Xu, Tae-Hoon Kim, Ping Lu, Laurent Bellaiche, Matthew J. Kramer, Xiaoli Tan, Lin Zhou. 2019-10-18. Uncompensated Polarization in Incommensurate Modulations of Perovskite Antiferroelectrics. https://doi.org/10.1103/physrevlett.123.217602

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