School of Physics, Georgia Institute of Technology, Atlanta, GA 30332, USA.
Sci Rep. 2013;3:1200. doi: 10.1038/srep01200. Epub 2013 Feb 4.
This work reports the first study of current-driven magnetization noise in a single, nanometerscale, ferromagnetic (Co) particle, attached to normal metal leads by high-resistance tunneling junctions. As the tunnel current increases at low temperature, the magnetic switching field decreases, its probability distribution widens, while the temperature of the environment remains nearly constant. These observations demonstrate nonequilibrium magnetization noise. A classical model of the noise is provided, where the spin-orbit interaction plays a central role in driving magnetic tunneling transitions.
本文报道了首例在单个纳米尺度铁磁（Co）粒子中电流驱动磁化噪声的研究，该粒子通过高电阻隧道结与正常金属引线相连。当隧道电流在低温下增加时，磁开关场减小，其概率分布变宽，而环境温度几乎保持不变。这些观察结果表明存在非平衡磁化噪声。本文提供了一种噪声的经典模型，其中自旋轨道相互作用在驱动磁隧道跃迁中起着核心作用。
