Helmholtz-Zentrum Dresden-Rossendorf, Institut für Ionenstrahlphysik und Materialforschung, D-01328 Dresden, Germany.
Technische Universität Dresden, 01062 Dresden, Germany.
Phys Rev Lett. 2019 Aug 2;123(5):057204. doi: 10.1103/PhysRevLett.123.057204.
In the last decade, two revolutionary concepts in nanomagnetism emerged from research for storage technologies and advanced information processing. The first suggests the use of magnetic domain walls in ferromagnetic nanowires to permanently store information in domain-wall racetrack memories. The second proposes a hardware realization of neuromorphic computing in nanomagnets using nonlinear magnetic oscillations in the gigahertz range. Both ideas originate from the transfer of angular momentum from conduction electrons to localized spins in ferromagnets, either to push data encoded in domain walls along nanowires or to sustain magnetic oscillations in artificial neurones. Even though both concepts share a common ground, they live on very different timescales which rendered them incompatible so far. Here, we bridge both ideas by demonstrating the excitation of magnetic auto-oscillations inside nanoscale domain walls using pure spin currents. This Letter will shed light on the current characteristic and spatial distribution of the excited auto-oscillations.
在过去的十年中，两项革命性的纳米磁学概念从存储技术和先进信息处理的研究中脱颖而出。第一个概念建议在铁磁纳米线中使用磁畴壁来在畴壁赛道记忆体中永久存储信息。第二个概念则提议在纳米磁体中使用千兆赫兹范围内的非线性磁振荡来实现神经形态计算的硬件实现。这两个想法都源于传导电子向铁磁体中局域自旋传递角动量，要么推动沿纳米线编码在畴壁中的数据，要么维持人工神经元中的磁振荡。尽管这两个概念有共同的基础，但它们处于非常不同的时间尺度，这使得它们迄今为止不兼容。在这里，我们通过使用纯自旋电流在纳米尺度畴壁中激发磁自激振荡来弥合这两个概念。这封信将阐明所激发的自激振荡的电流特性和空间分布。
