Dynamics of topological magnetic textures are typically induced externally by, e.g.~magnetic fields or spin/charge currents. Here, we demonstrate the effect of the internal-to-the-system geometry-induced motion of a domain wall in a curved nanostripe. Being driven by the gradient of the curvature of a biaxial stripe, transversal domain walls acquire remarkably high velocities of up to 100 m/s and do not exhibit any Walker-type speed limit. We pinpoint that the inhomogeneous distribution of the curvature-induced Dzyaloshinskii--Moriya interaction is a driving force for the motion of a domain wall. Although we showcase our approach on the specific Euler spiral geometry, the approach is general and can be applied to a wide class of geometries.
研究了$U (1)$规范场对具有弯曲畴壁质量项的格点费米子系统的影响。与传统的平畴壁费米子一样，手征边缘模出现在壁面，其Dirac算符包含诱导引力势和$U(1)$矢量势。对于二维平面晶格上的$S^1$畴壁费米子，我们发现Aharonov-Bohm（AB）效应与引力能隙之间存在竞争，导致时间反演（$T$）对称性的反常.我们的数值结果表明，在$S^1$畴壁内的圆盘上，Atiyah-Patodi-Singer指数定理是一致的，该定理描述了主体和边缘之间的$T$异常的抵消。当$U(1)$通量压缩在一个元胞内，AB相取量子化值$π$ mod $2π\mathbb{Z}$时，反常入流发生剧烈变化：强通量在通量周围产生另一个畴壁，使两个零模共存。这种现象也被观察到在$S^2$畴壁费米子中的磁性粒子的存在。我们发现，畴壁周围的创造微观解释了威滕效应。
TetMaG-Guided Design and Operando Electron Holography Validation of Current-Induced Domain-Wall Motion in 3D Curved and Cornered Fe Nanobridges
SUPA, School of Physics and Astronomy, University of Glasgow（格拉斯哥大学物理与天文学学院）；Institute for Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf（德累斯顿-罗斯多夫亥姆霍兹中心离子束物理与材料研究所）；Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons（恩斯特·鲁斯卡电子显微镜与谱学中心）
Geodesic geometry of 2+1-D Dirac materials subject to artificial, quenched gravitational singularities
Condensed Matter Theory Center and Joint Quantum Institute, Department of Physics, University of Maryland（马里兰大学凝聚态理论中心与联合量子研究所）；Department of Physics and Astronomy and Rice Center for Quantum Materials, Rice University（莱斯大学物理与天文学系及量子材料中心）
