Compact merons and skyrmions in thin chiral magnetic films
Compact merons and skyrmions in thin chiral magnetic films
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DOI：
10.1103/physrevb.83.100408
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发表时间：
2011-03-18
影响因子：
3.7
通讯作者：
Ezawa, Motohiko
中科院分区：
文献类型：
--
作者：
Ezawa, Motohiko
半子是一种有争议的拓扑激发态，因为它只携带斯格明子数的一半。磁性薄膜中的涡旋被认为是半斯格明子，即半斯格明子。我们提出了另一种类型的 meron，研究二维非线性 sigma 模型以及 Dzyaloshinskii-Moriya 相互作用。这里，Meron 的涡数为零。基本的拓扑激发是麦伦子和斯格明子。它们的行为就像自由粒子一样。一个突出的特点是拓扑电荷密度严格限制在紧凑域内。我们提出了一种针对这些紧凑激励的分析方法，并构建了相图。它由螺旋相、半子相、斯格明子晶体、斯格明子气体和铁磁体相组成。它捕捉了最近在 MnSi 和 FeCoSi 薄膜等手性磁体中进行的实验数据的本质。
A meron is a controversial topological excitation because it carries just one-half of the skyrmion number. A vortex in thin magnetic films has been argued to be a half-skyrmion, i.e., a meron. We present another type of merons, investigating the two-dimensional nonlinear sigma model together with the Dzyaloshinskii-Moriya interaction. Here, the vortex number of a meron is zero. Basic topological excitations are merons and skyrmions. They behave as if they were free particles. A prominent feature is that the topological charge density is strictly confined within compact domains. We propose an analytic approach for these compact excitations, and construct a phase diagram. It is comprised of the helix, meron, skyrmion-crystal, skyrmion-gas, and ferromagnet phases. It captures the essential nature of the experimental data recently performed in chiral magnets such as MnSi and FeCoSi thin films.