First-principles study of nanometer-sharp domain walls in ferromagnetic Fe monolayers under in-plane strain
First-principles study of nanometer-sharp domain walls in ferromagnetic Fe monolayers under in-plane strain
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DOI：
10.1088/0953-8984/24/9/095303
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发表时间：
2012-03
期刊：
影响因子：
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通讯作者：
T. Shimada;J. Okuno;Y. Ishii;T. Kitamura
中科院分区：
文献类型：
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作者：
T. Shimada;J. Okuno;Y. Ishii;T. Kitamura
我们研究了一个纳米级的尖锐磁畴壁（DW）结构在一个独立的Fe（110）单层和研究的关键作用面内应变使用完全无约束的非共线从头计算自旋密度泛函理论计算在广义梯度近似。DW宽度计算为0.86 nm。一个精确的矢量场描述的磁化强度密度显示，在DW中的非共线字符空间上被限制在原子之间，而共线和高磁化强度密度被定位在每个原子周围。在DW中磁矩的快速旋转中，我们发现由于能带结构的移动，电子从dzx和dx2−y2态重排到dxy，dyz和dz2态。施加拉伸和压缩的面内应变都带来更窄的DW在单层膜中，除了当应变小。的DW宽度的应变依赖性进行了讨论交换相互作用和磁晶各向异性。
We investigated a nanometer-sharp magnetic domain wall (DW) structure in a free-standing Fe(110) monolayer and studied the crucial role of in-plane strain using fully unconstrained noncollinear ab initio spin-density-functional theory calculations within the generalized gradient approximation. The DW width is calculated to be 0.86 nm. A precise vector-field description of the magnetization density revealed that a noncollinear character in the DW was spatially confined between atoms, whereas a collinear and high magnetization density was localized around each atom. In the rapid rotation of magnetic moments in the DW, we found an electron rearrangement from the dzx and dx2−y2 states to the dxy, dyz and dz2 states due to a shift of band structures. Applied tensile and compressive in-plane strains both bring about narrower DWs in the monolayer except when the strain is small. The strain dependence of the DW width is discussed in terms of both exchange interaction and magnetocrystalline anisotropy.