论文标题
在反铁磁绝缘子和二维金属的界面上通过移动域壁旋转泵送
Spin pumping by a moving domain wall at the interface of an antiferromagnetic insulator and a two-dimensional metal
论文作者
论文摘要
与抗铁磁绝缘子（AFMI）和二维（2D）金属之间平行移动的域壁（DW），可以平行地移动到磁补偿的界面。假定共线AFMI的局部旋转通过界面上的交换相互作用与巡回电子相互作用。我们利用了Keldysh Green的功能的形式，这些功能在随机杂质上经历潜在的和旋转的轨道散射。这种形式主义允许对2D电子气体的自旋泵送，自旋扩散和自旋松弛影响进行统一分析。结果表明，对于界面交换相互作用，未插入的磁化材料泵送到金属膜中。在足够弱的自旋松弛下，这种抽水效应可能比保利磁力的一阶效应要强得多，而Pauli磁性是由小型DW的小型非交换场产生的。结果表明，泵送的极化对电子费米表面的几何形状敏感，并且当交错磁化的波向量接近费米表面的嵌套载体时增加。在无序的扩散电子气体中，诱导的自旋极化遵循域壁的运动。它在DW周围不对称地分布在距离上，该距离可能比DW宽度大得多。
A domain wall (DW) which moves parallel to a magnetically compensated interface between an antiferromagnetic insulator (AFMI) and a two-dimensional (2D) metal can pump spin polarization into the metal. It is assumed that localized spins of a collinear AFMI interact with itinerant electrons through their exchange interaction on the interface. We employed the formalism of Keldysh Green's functions for electrons which experience potential and spin-orbit scattering on random impurities. This formalism allows a unified analysis of spin pumping, spin diffusion and spin relaxation effects on a 2D electron gas. It is shown that the pumping of a nonstaggered magnetization into the metal film takes place in the second order with respect to the interface exchange interaction. At sufficiently weak spin relaxation this pumping effect can be much stronger than the first-order effect of the Pauli magnetism which is produced by the small nonstaggered exchange field of the DW. It is shown that the pumped polarization is sensitive to the geometry of the electron's Fermi surface and increases when the wave vector of the staggered magnetization approaches the nesting vector of the Fermi surface. In a disordered diffusive electron gas the induced spin polarization follows the motion of the domain wall. It is distributed asymmetrically around the DW over a distance which can be much larger than the DW width.
