Gao Botao, Zhou Wenjie, Liu Hui, Qi He, Deng Shiqing, Liu Shi, Chen Jun
Beijing Advanced Innovation Center for Materials Genome Engineering, Department of Physical Chemistry, University of Science and Technology Beijing, Beijing 100083, China.
Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, Shanghai 201899, China.
Nano Lett. 2023 Feb 8;23(3):948-953. doi: 10.1021/acs.nanolett.2c04361. Epub 2023 Jan 30.
Electric-field-induced antiferroelectric-ferroelectric (AFE-FE) phase transition is a prominent feature of antiferroelectric (AFE) materials. The critical electric field of this phase transition is crucial for the device performance of AEFs in many applications, but the determining factor of the critical electric field is still unclear. Here, we have established the correlation between the underlying structure and the critical electric field by using synchrotron X-ray diffraction and high-resolution neutron diffraction in Pb(Zr,Sn,Ti)O-based antiferroelectrics. It is found that the critical electric field is determined by the angle between the average polarization vector in the incommensurate AFE state and the [111] polarization direction in the rhombohedral FE state. A large polarization rotation angle gives rise to a large critical electric field. Further, density functional theory (DFT) calculations corroborate that the lower energy is required for driving a smaller angle polarization rotation. Our discovery will offer guidance to optimize the performance of AFE materials.
电场诱导的反铁电-铁电（AFE-FE）相变是反铁电（AFE）材料的一个显著特征。这一相变的临界电场对于AFE在许多应用中的器件性能至关重要，但临界电场的决定因素仍不明确。在此，我们通过在基于Pb(Zr,Sn,Ti)O的反铁电体中使用同步加速器X射线衍射和高分辨率中子衍射，建立了底层结构与临界电场之间的关联。研究发现，临界电场由非公度AFE态下的平均极化矢量与菱面体FE态下的[111]极化方向之间的夹角决定。较大的极化旋转角会产生较大的临界电场。此外，密度泛函理论（DFT）计算证实，驱动较小角度的极化旋转所需的能量较低。我们的发现将为优化AFE材料的性能提供指导。
