Solitary wave excitations of skyrmion strings in chiral magnets
Solitary wave excitations of skyrmion strings in chiral magnets
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DOI：
10.1103/physrevb.102.220408
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发表时间：
2020-12-17
影响因子：
3.7
通讯作者：
Garst, Markus
中科院分区：
文献类型：
--
作者：
Kravchuk, Volodymyr P.;Rossler, Ulrich K.;Garst, Markus
手性磁体具有拓扑线激励，其中每个横截面内的磁化形成斯基子织构。我们对场极化立方手性磁体中这种斯基子弦的低能非线性动力学进行了解析和数值研究，并证明了它支持孤波。这些波通常是非互易的，也就是说，它们的性质取决于它们的速度v的符号，但这种非互易性随着垂直杆v的减小而减小。导出了孤立波在极限v -> 0下有效的场理论描述，并给出了它们的剖面和存在状态。我们的分析结果定量地证实了微磁模拟参数适合手性磁体FeGe。指出了流体涡旋细丝与孤立波的相似之处。
Chiral magnets possess topological line excitations where the magnetization within each cross section forms a skyrmion texture. We study analytically and numerically the low-energy, nonlinear dynamics of such a skyrmion string in a field-polarized cubic chiral magnet, and we demonstrate that it supports solitary waves. These waves are in general nonreciprocal, i.e., their properties depend on the sign of their velocity v, but this nonreciprocity diminishes with decreasing vertical bar v vertical bar. An effective field-theoretical description of the solitary waves is derived that is valid in the limit v -> 0 and gives access to their profiles and their existence regime. Our analytical results are quantitatively confirmed with micromagnetic simulations for parameters appropriate for the chiral magnet FeGe. Similarities with solitary waves found in vortex filaments of fluids are pointed out.