论文标题
在W-TA合金中增强自旋霍尔电导率
Enhancement of spin Hall conductivity in W-Ta alloy
论文作者
论文摘要
在过去十年中，通过重金属以旋转厅效应生成纯自旋电流一直是研究的主题。为了减少有效切换相邻铁磁层所需的能量，不仅应提高电荷到旋转转换效率，而且还应降低重金属的纵向电阻率。在这项工作中，我们使用自旋扭矩铁磁共振测量值调查了W_ {1 -X} ta_ {1 -X} ta_ {x} / cofeb / mgo（x = 0-0.2）中的自旋电导率。与TA合金W的合金w会导致两次变化的倍数变化，在阻尼样有效的旋转霍尔角（从-0.15到-0.3）和纵向电阻率（60-120μwcm）。在11％TA浓度下，使用低纵向电阻率100μWcm实现了非常高的旋转霍尔角值-0.3，这可能会导致这种基于W的合金的功耗非常低。这项工作表明，溅射沉积的W-TA合金可能是发挥旋转电流的有前途的材料。
Generating pure spin currents via the spin Hall effect in heavy metals has been an active topic of research in the last decade. In order to reduce the energy required to efficiently switch neighbouring ferromagnetic layers for applications, one should not only increase the charge- to-spin conversion efficiency but also decrease the longitudinal resistivity of the heavy metal. In this work, we investigate the spin Hall conductivity in W_{1-x}Ta_{x} / CoFeB / MgO (x = 0 - 0.2) using spin torque ferromagnetic resonance measurements. Alloying W with Ta leads to a factor of two change in both the damping-like effective spin Hall angle (from - 0.15 to - 0.3) and longitudinal resistivity (60 - 120 μW cm). At 11% Ta concentration, a remarkably high spin Hall angle value of - 0.3 is achieved with a low longitudinal resistivity 100 μW cm, which could lead to a very low power consumption for this W-based alloy. This work demonstrates sputter-deposited W-Ta alloys could be a promising material for power-efficient spin current generation.
