Direct observation of the polar state in the relaxor Ba(Ti 1-xZrx)O3 by transmission electron microscopy

H. Tsukasaki*, Y. Inoue, Y. Koyama

*この研究の対応する著者

研究成果: Article査読

2 被引用数 (Scopus)

抄録

In the ferroelectric mixed-oxide system Ba(Ti1-xZr x)O3 (BTZ), an increase in Zr content results in the crossover from the ferroelectric MA-type state with monoclinic symmetry to the relaxor state around x = 0.28. As a result of the crossover, BTZ is identified as the relaxor for x > 0.28. To understand the nature of the relaxor in BTZ, direct observations of the paraelectric (PE), MA, and relaxor states for 0.17 ≤ x ≤ 0.40 was carried out between 400 K and 87 K by transmission electron microscopy with the help of the failure of Friedel's law. The observations indicated that polar nanometer-sized regions with <110>PE and <001>PE components were separately observed in the PE state above both Tc and Tm, which are, respectively, a transition temperature of the direct (PE→MA) transition and a maximum temperature of the real dielectric permittivity for the relaxor. During cooling from the paraelectric state above Tm in the relaxor, in the relaxor state below it, <001>PC-component regions locally formed a 180° domain structure, together with no coalescence of <110>PC regions. It is thus understood that the M A-to-relaxor crossover is characterized by the complete suppression of the coalescence of polar nanometer-sized regions with <110> PE components. The relaxor state below Tm for 0.29 ≤ x ≤ 0.40 could be, as a result, identified as an assembly of polar nanometer-sized domains, presumably with monoclinic symmetry.

本文言語English
ページ(範囲)18-33
ページ数16
ジャーナルFerroelectrics
460
1
DOI
出版ステータスPublished - 2014 2 17

ASJC Scopus subject areas

  • 電子材料、光学材料、および磁性材料
  • 凝縮系物理学

フィンガープリント

「Direct observation of the polar state in the relaxor Ba(Ti <sub>1-x</sub>Zr<sub>x</sub>)O<sub>3</sub> by transmission electron microscopy」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル