arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1003.0660cond-mat.mtrl-sci
收藏

拉曼光谱研究(Bi0 0.5)TiO3-BaTiO3的结构复杂性

The Structural Complexity of (Bi0.5Na0.5)TiO3-BaTiO3 as Revealed by Raman Spectroscopy

Ben Wylie-van Eerd, Dragan Damjanovic, Naama Klein, Nava Setter, Joe Trodahl

摘要:

用Raman光谱研究了(Na_(1/2)Bi_(1/2))_(1-x)TiO_3(NBT-BT)(x<0.1)在10 ~ 470 K温度范围内的结构相图。这些数据提供了明确的证据,提出了温度无关的morphotropic相界在x \approx 0.055。然而,没有证据表明,在T \approx 370 K的结构相变x > 0.055,其中体属性异常出现信号过渡到非极性或反铁电相。结果表明,370 K以上的相显示出与370 K以下的长程有序相相同的短程离子位移。这些结论提供了一个自然的解释,在这个系统中的弱压电响应,并具有重要的意义,为无铅压电材料的搜索。

英文摘要:

The structural phase diagram of the Pb-free ferroelectric (Na1/2Bi1/2)1-xBaxTiO3 (NBT-BT), x<0.1, has been explored by Raman spectroscopy at temperatures from 10 to 470 K. The data provide clear evidence for a proposed temperature-independent morphotropic phase boundary at x \approx 0.055. However, there is no evidence for a structural phase transition across T \approx 370 K for x > 0.055, where bulk-property anomalies appear to signal a transition to a nonpolar or antiferroelectric phase. The results identify that the phase above 370 K shows short-range ionic displacements that are identical to those in the long-range-ordered phase below 370 K. These conclusions provide a natural interpretation of the weak piezoelectric response in this system and have important implications for the search for Pb-free piezoelectrics.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑