Abstract The vast majority of studies on field-induced changes in (1–x)Pb(Mg1/3Nb2/3)O3–xPbTiO3 (PMN–xPT) materials at the morphotropic phase boundary (MPB) have been performed on single crystals, while the more complex responses in polycrystalline materials have not yet been resolved. By using combined microscopy and diffraction techniques, this study aims to determine the structural changes induced by application of an electric field to two representative MPB compositions of the PMN–xPT family, namely, PMN–30PT with the initial Cm and Pm coexisting phases, and PMN–35PT with the P4mm and Pm phases. Both ceramic compositions are characterized by a hierarchical domain structure with domains present at different length-scales. Based on the applied field measurements, major contributing effects in both compositions are outlined and discussed with respect to the processes related to the monoclinic phase and the adaptive phase theory. It is shown that the highly mobile domain walls are largely involved, along with the field-induced polarization rotation in the monoclinic PMN–30PT, and a phase transition to a mainly tetragonal structure in PMN–35PT. These multiscale results elucidate important aspects of field-induced changes in PMN–xPT materials, contributing to the understanding of the complex electrical and electromechanical response of relaxor ferroelectrics.

中文翻译：

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(1- x )Pb(Mg 1/3 Nb 2/3 )O 3 – x PbTiO 3 陶瓷的多尺度场致结构来自组合技术

摘要 绝大多数关于 (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 (PMN-xPT) 材料在同形相界 (MPB) 中场致变化的研究都是在单晶上进行的，而多晶材料中更复杂的响应尚未解决。通过使用组合显微镜和衍射技术，本研究旨在确定将电场应用于 PMN-xPT 家族的两种代表性 MPB 组合物，即具有初始 Cm 和 Pm 共存相的 PMN-30PT 所引起的结构变化，以及具有 P4mm 和 Pm 相位的 PMN-35PT。两种陶瓷组合物的特征在于具有以不同长度尺度存在的域的分级域结构。根据应用现场测量，关于与单斜相和自适应相理论相关的过程，概述和讨论了两种组合物中的主要贡献效应。结果表明，高度移动的畴壁在很大程度上与单斜 PMN-30PT 中的场致极化旋转以及 PMN-35PT 中主要为四方结构的相变有关。这些多尺度结果阐明了 PMN-xPT 材料中场致变化的重要方面，有助于理解弛豫铁电体的复杂电气和机电响应。以及在 PMN-35PT 中向主要四方结构的相变。这些多尺度结果阐明了 PMN-xPT 材料中场致变化的重要方面，有助于理解弛豫铁电体的复杂电气和机电响应。以及在 PMN-35PT 中向主要四方结构的相变。这些多尺度结果阐明了 PMN-xPT 材料中场致变化的重要方面，有助于理解弛豫铁电体的复杂电气和机电响应。