Efficient manipulation of antiferromagnetically coupled materials that are integration-friendly and have strong perpendicular magnetic anisotropy (PMA) is of great interest for low-power, fast, dense magnetic storage and computing. Here, we report a distinct, giant bulk damping-like spin–orbit torque in strong-PMA ferrimagnetic Fe100− xTb x single layers that are integration-friendly (composition-uniform, amorphous, and sputter-deposited). For sufficiently thick layers, this bulk torque is constant in the efficiency per unit layer thickness, [Formula: see text]/ t, with a record-high value of 0.036 ± 0.008 nm−1, and the damping-like torque efficiency [Formula: see text] achieves very large values for thick layers, up to 300% for 90 nm layers. This giant bulk torque by itself switches tens of nm thick Fe100− xTb x layers that have very strong PMA and high coercivity at current densities as low as a few MA/cm2. Surprisingly, for a given layer thickness, [Formula: see text] shows strong composition dependence and becomes negative for composition where the total angular momentum is oriented parallel to the magnetization rather than antiparallel. Our findings of giant bulk spin torque efficiency and intriguing torque-compensation correlation will stimulate study of such unique spin–orbit phenomena in a variety of ferrimagnetic hosts. This work paves a promising avenue for developing ultralow-power, fast, dense ferrimagnetic storage and computing devices.

中文翻译：

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具有强垂直磁各向异性的单个亚铁磁 FeTb 层中的巨大体积自旋轨道力矩和高效电开关

高效操纵集成友好且具有强垂直磁各向异性 (PMA) 的反铁磁耦合材料对于低功耗、快速、高密度磁存储和计算具有重要意义。在这里，我们报告了强 PMA 亚铁磁 Fe 中明显的、巨大的体积阻尼类自旋轨道力矩100−XTBX易于集成的单层（成分均匀、非晶和溅射沉积）。对于足够厚的层，这种体积扭矩在每单位层厚度的效率中是恒定的，[公式：见文本]/ t，具有创纪录的 0.036 ± 0.008 nm 的值−1，并且类似阻尼的转矩效率 [公式：见文本] 对厚层实现了非常大的值，对于 90 nm 层高达 300%。这个巨大的体积扭矩本身会切换数十纳米厚的 Fe100−XTBX在低至几个 MA/cm 的电流密度下具有非常强的 PMA 和高矫顽力的层2个. 令人惊讶的是，对于给定的层厚度，[公式：见文本] 显示出强烈的成分依赖性，并且对于总角动量平行于磁化而非反平行的成分的成分变为负数。我们对巨大体积自旋扭矩效率和有趣的扭矩补偿相关性的发现将刺激对各种亚铁磁性主体中这种独特的自旋轨道现象的研究。这项工作为开发超低功耗、快速、密集的亚铁磁存储和计算设备铺平了道路。