中国物理B ›› 2024, Vol. 33 ›› Issue (11): 118502-118502.doi: 10.1088/1674-1056/ad8cbc
所属专题： SPECIAL TOPIC — Stephen J. Pennycook: A research life in atomic-resolution STEM and EELS
Polarization pinning at antiphase boundaries in multiferroic YbFeO3
Guodong Ren1, Pravan Omprakash1, Xin Li2, Yu Yun2,3, Arashdeep S. Thind1, Xiaoshan Xu2,4, and Rohan Mishra5,1,†
- 1 Institute of Materials Science and Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA;
2 Department of Physics and Astronomy, University of Nebraska, Lincoln, NE 68588, USA;
3 Department of Mechanical Engineering & Mechanics, Drexel University, Philadelphia, PA 19104-2875, USA;
4 Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, NE 68588, USA;
5 Department of Mechanical Engineering and Material Science, Washington University in St. Louis, St. Louis, MO 63130, USA
Polarization pinning at antiphase boundaries in multiferroic YbFeO3
Guodong Ren1, Pravan Omprakash1, Xin Li2, Yu Yun2,3, Arashdeep S. Thind1, Xiaoshan Xu2,4, and Rohan Mishra5,1,†
- 1 Institute of Materials Science and Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA;
2 Department of Physics and Astronomy, University of Nebraska, Lincoln, NE 68588, USA;
3 Department of Mechanical Engineering & Mechanics, Drexel University, Philadelphia, PA 19104-2875, USA;
4 Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, NE 68588, USA;
5 Department of Mechanical Engineering and Material Science, Washington University in St. Louis, St. Louis, MO 63130, USA
摘要： The switching characteristics of ferroelectrics and multiferroics are influenced by the interaction of topological defects with domain walls. We report on the pinning of polarization due to antiphase boundaries in thin films of the multiferroic hexagonal YbFeO$_{3}$. We have directly resolved the atomic structure of a sharp antiphase boundary (APB) in YbFeO$_{3}$ thin films using a combination of aberration-corrected scanning transmission electron microscopy (STEM) and total energy calculations based on density-functional theory (DFT). We find the presence of a layer of FeO$_{6}$ octahedra at the APB that bridges the adjacent domains. STEM imaging shows a reversal in the direction of polarization on moving across the APB, which DFT calculations confirm is structural in nature as the polarization reversal reduces the distortion of the FeO$_{6}$ octahedral layer at the APB. Such APBs in hexagonal perovskites are expected to serve as domain-wall pinning sites and hinder ferroelectric switching of the domains.
中图分类号: (Ferrite and garnet devices)
- 85.70.Ge