Relativistic kinematics of a magnetic soliton
Relativistic kinematics of a magnetic soliton
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DOI：
10.1126/science.aba5555
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发表时间：
2020-12-18
期刊：
影响因子：
56.9
通讯作者：
Beach, Geoffrey S. D.
中科院分区：
文献类型：
--
作者：
Caretta, Lucas;Oh, Se-Hyeok;Beach, Geoffrey S. D.
狭义相对论的一个原则是，任何粒子都不能超过光速。在某些磁性材料中，最大磁振子群速度作为磁孤子速度的类似相对论极限。在这里，我们使用来自自旋霍尔效应的纯自旋电流，在低耗散磁绝缘体中将磁畴壁驱动到这个极限。我们获得了创纪录的电流驱动速度，超过每秒4300米--接近相对论极限的10%--我们观察到与洛伦兹收缩相关的相对论运动的关键特征，这会导致速度饱和。实验结果通过分析和原子模拟得到了很好的解释。这些观察结果提供了对磁孤子动力学基本极限的重要洞察，并建立了一个易于访问的实验框架来研究相对论孤子物理。
A tenet of special relativity is that no particle can exceed the speed of light. In certain magnetic materials, the maximum magnon group velocity serves as an analogous relativistic limit for the speed of magnetic solitons. Here, we drive domain walls to this limit in a low-dissipation magnetic insulator using pure spin currents from the spin Hall effect. We achieve record current-driven velocities in excess of 4300 meters per second-within similar to 10% of the relativistic limit-and we observe key signatures of relativistic motion associated with Lorentz contraction, which leads to velocity saturation. The experimental results are well explained through analytical and atomistic modeling. These observations provide critical insight into the fundamental limits of the dynamics of magnetic solitons and establish a readily accessible experimental framework to study relativistic solitonic physics.