Probing the Nanodomain Origin and Phase Transition Mechanisms in (Un)Poled PMN-PT Single Crystals and Textured Ceramics

Materials

Aneta Slodczyk¹ 

[1] Laboratoire de Dynamique, Interactions et Réactivité (LADIR), UMR 7075, CNRS, UPMC, 2 rue H. Dunant 94320 Thiais, France; E-Mail

关键词: PMN-PT;    ferroelectric relaxor;    piezoelectric;    Raman scattering;    solid solutions;   

DOI  :  10.3390/ma3125007

来源: mdpi

【 摘 要 】

Outstanding electrical properties of solids are often due to the composition heterogeneity and/or the competition between two or more sublattices. This is true for superionic and superprotonic conductors and supraconductors, as well as for many ferroelectric materials. As in PLZT ferroelectric materials, the exceptional ferro- and piezoelectric properties of the PMN-PT ((1−x)PbMg_1/3Nb_2/3O₃−xPbTiO₃) solid solutions arise from the coexistence of different symmetries with long and short scales in the morphotropic phase boundary (MPB) region. This complex physical behavior requires the use of experimental techniques able to probe the local structure at the nanoregion scale. Since both Raman signature and thermal expansion behavior depend on the chemical bond anharmonicity, these techniques are very efficient to detect and then to analyze the subtitle structural modifications with an efficiency comparable to neutron scattering. Using the example of poled (field cooling or room temperature) and unpoled PMN-PT single crystal and textured ceramic, we show how the competition between the different sublattices with competing degrees of freedom, namely the Pb-Pb dominated by the Coulombian interactions and those built of covalent bonded entities (NbO₆ and TiO₆), determine the short range arrangement and the outstanding ferro- and piezoelectric properties.

【 授权许可】

CC BY   
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