First-principles study of ferroelectric domain walls in multiferroic bismuth ferrite
First-principles study of ferroelectric domain walls in multiferroic bismuth ferrite
复制标题
DOI：
10.1103/physrevb.80.104110
复制
发表时间：
2009-09-01
影响因子：
3.7
通讯作者：
Spaldin, N. A.
中科院分区：
文献类型：
--
作者：
Lubk, Axel;Gemming, S.;Spaldin, N. A.
我们提出了第一性原理密度泛函研究的结构，电子和磁性的铁电畴壁的多铁性BiFeO 3。我们发现，畴壁中的氧八面体的旋转不改变它们的相位时，极化重定向是最有利的，这些，109度畴壁中心周围的BiO平面具有最低的能量。109度和180度的壁在垂直于壁的极化分量上有显着的变化;静电势的相应步骤与最近关于畴壁电导率的报告一致。最后，我们表明，在畴壁的Fe-O-Fe键角的变化引起的Fe磁矩的倾斜，这可以提高在畴壁的局部磁化的变化。
We present a first-principles density-functional study of the structural, electronic, and magnetic properties of the ferroelectric domain walls in multiferroic BiFeO3. We find that domain walls in which the rotations of the oxygen octahedra do not change their phase when the polarization reorients are the most favorable and of these, the 109 degrees domain wall centered around the BiO plane has the lowest energy. The 109 degrees and 180 degrees walls have a significant change in the component of their polarization perpendicular to the wall; the corresponding step in the electrostatic potential is consistent with a recent report of electrical conductivity at the domain walls. Finally, we show that changes in the Fe-O-Fe bond angles at the domain walls cause changes in the canting of the Fe magnetic moments which can enhance the local magnetization at the domain walls.