论文标题
旋转厅角，自旋混合电导和旋转扩散长度的测定IR/COFEB的自旋轨道设备
Determination of the spin Hall angle, spin mixing conductance and spin diffusion length in Ir/CoFeB for spin-orbitronic devices
论文作者
论文摘要
由于其有趣的磁性特性，例如大的rkky交换耦合以及其大型自旋轨道耦合值，因此虹膜是自旋应用的一种非常有前途的材料。例如，IR用作垂直合成抗铁磁或铁磁体系统的间隔层。但是，仅报道了该材料的自旋特性参数的少数研究。在本文中，我们提出了反旋转大厅的效应 - 基于COFEB/IR的双层旋转泵送铁电磁共振测量值，以估计有效自旋霍尔角的值，Iridium内的旋转扩散长度以及COFEB/IR IR BiLayer中的自旋扩散长度以及自旋混合电导。为了获得可靠的结果，我们对COFEB/PT双层进行了相同的实验，这是由于许多报道的研究而众所周知的。 Our experimental results show that the spin diffusion length within iridium is 1.3 nm for resistivity of 250 n$Ω$.m, the spin mixing conductance $g_{eff}^{\uparrow \downarrow}$ of the CoFeB/Ir interface is 30 nm$^{-2}$, and the spin Hall angle of iridium has the same sign than the one of platinum and is evaluated at 26% of the铂金之一。发现PT的旋转厅角度为7.7％，IR的值为2％。这些相关参数对于在结合旋转轨道扭矩和自旋转移扭矩的新概念和设备中考虑IR应该很有用。
Iridium is a very promising material for spintronic applications due to its interesting magnetic properties such as large RKKY exchange coupling as well as its large spin-orbit coupling value. Ir is for instance used as a spacer layer for perpendicular synthetic antiferromagnetic or ferrimagnet systems. However, only a few studies of the spintronic parameters of this material have been reported. In this paper, we present inverse spin Hall effect - spin pumping ferromagnetic resonance measurements on CoFeB/Ir based bilayers to estimate the values of the effective spin Hall angle, the spin diffusion length within iridium, and the spin mixing conductance in the CoFeB/Ir bilayer. In order to have reliable results, we performed the same experiments on CoFeB/Pt bilayers, which behavior is well known due to numerous reported studies. Our experimental results show that the spin diffusion length within iridium is 1.3 nm for resistivity of 250 n$Ω$.m, the spin mixing conductance $g_{eff}^{\uparrow \downarrow}$ of the CoFeB/Ir interface is 30 nm$^{-2}$, and the spin Hall angle of iridium has the same sign than the one of platinum and is evaluated at 26% of the one of platinum. The value of the spin Hall angle found is 7.7% for Pt and 2% for Ir. These relevant parameters shall be useful to consider Ir in new concepts and devices combining spin-orbit torque and spin-transfer torque.
