论文标题
NIO中的现场辅助子terahertz旋转和自动振荡
Field-Assisted Sub-Terahertz Spin Pumping and Auto-Oscillation in NiO
论文作者
论文摘要
最近在具有易于轴磁各向异性的抗铁磁铁（AFMS）中证明了转换为DC自旋电流转换为DC自旋电流的自旋泵送。但是，易于在实验上更容易准备的NIO等易于平面AFM被认为是旋转泵送的不良候选者，因为NéelVector振荡是线性极化的，对实用应用的材料选择构成了重大限制。通过对NIO的案例研究，我们表明，自旋流动过渡下方的施加磁场可以实质性地改变谐振特征模的极化，从而使相干的亚terahertz旋转泵泵在易于轴AFMS中一样强。此外，我们发现施加的磁场可以显着降低由自旋转移扭矩触发的Néel载体自动振荡的阈值。这些突出的现场辅助效应可以极大地促进次赫兹频率制度中的自旋装置工程。
Spin pumping converting sub-terahertz electromagnetic waves to DC spin currents has recently been demonstrated in antiferromagnets (AFMs) with easy-axis magnetic anisotropy. However, easy-plane AFMs such as NiO, which are easier to prepare experimentally, are considered to be bad candidates for spin pumping because the Néel vector oscillation is linearly polarized, placing a major restriction on the material choice for practical applications. Through a case study of NiO, we show that an applied magnetic field below the spin-flop transition can substantially modify the polarization of the resonance eigenmodes, which enables coherent sub-terahertz spin pumping as strong as that in easy-axis AFMs. In addition, we find that an applied magnetic field can significantly reduce the threshold of Néel vector auto-oscillation triggered by spin-transfer torques. These prominent field-assisted effects can greatly facilitate spintronic device engineering in the sub-terahertz frequency regime.
