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Universal Phase Diagram for High-Piezoelectric Perovskite Systems

D. E. Cox·B. Noheda·G. Shirane·Y. Uesu·K. Fujishiro·Y. Yamada
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Abstract

Strong piezoelectricity in the perovskite-type PbZr(1-x)TixO3 (PZT) and Pb(Zn1/3Nb2/3)O3-PbTiO3 (PZN-PT) systems is generally associated with the existence of a morphotropic phase boundary (MPB) separating regions with rhombohedral and tetragonal symmetry. An x-ray study of PZN-9%PT has revealed the presence of a new orthorhombic phase at the MPB, and a near-vertical boundary between the rhombohedral and orthorhombic phases, similar to that found for PZT between the rhombohedral and monoclinic phases. We discuss the results in the light of a recent theoretical paper by Vanderbilt and Cohen, which attributes these low-symmetry phases to the high anharmonicity in these oxide systems.

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D. E. Cox, B. Noheda, G. Shirane, Y. Uesu, K. Fujishiro, Y. Yamada. 2001-02-25. Universal Phase Diagram for High-Piezoelectric Perovskite Systems. https://doi.org/10.1063/1.1384475

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