论文标题
直接观察局部抗抗抗抗逆抗诱导的声子在SRTIO3缺陷处的变形
Direct observation of local antiferroelectricity induced phonon softening at a SrTiO3 defect
论文作者
论文摘要
氧化物中的缺陷通常表现出可能与局部晶格动力学相关的外来特性。在这里，在原子空间分辨率下，我们直接测量了SRTIO3独立膜中反相边界（APB）的声子模式，并将它们与图表级的结构失真相关联。我们发现SRTIO3 APB引入了大量SRTIO3中不存在的新缺陷声子模式。这些模式对微妙的结构失真高度敏感，即SRTIO3 APB会产生局部的电偶极子形成抗纤维自由构型，从而显着柔和γ点处的横向光学（TO）和纵向光学（TO）和纵向光学（LO）。将局部声子与微妙的结构失真相关联，我们的发现为了解复杂氧化物中的缺陷特性以及其应用（例如热电设备）的基本信息提供了宝贵的见解。
Defects in oxides usually exhibit exotic properties that may be associated with the local lattice dynamics. Here, at atomic spatial resolution, we directly measure phonon modes of an antiphase boundary (APB) in SrTiO3 freestanding membrane and correlate them with the picometer-level structural distortion. We find that the SrTiO3 APB introduces new defect phonon modes that are absent in bulk SrTiO3. These modes are highly sensitive to the subtle structure distortion, i.e., the SrTiO3 APB generates the local electric dipoles forming an antiferroelectric configuration, which significantly softens the transverse optical (TO) and longitudinal optical (LO) modes at Γ point. Correlating the local phonons with the subtle structural distortion, our findings provide valuable insights into understanding the defect properties in complex oxides and essential information for their applications such as thermoelectric devices.
