Recently spin textures called skyrmions have been discovered in certain chiral magnetic materials without spatial inversion symmetry, and have attracted enormous attention due to their promising application in spintronics since only a low applied current is necessary to drive their motion. When a conduction electron moves around the skyrmion, its spin is fully polarized by the spin texture and acquires a quantized phase; thus, the skyrmion yields an emergent electrodynamics that in turn determines skyrmion motion and gives rise to a finite Hall angle. While Skyrmions behave as particles, no particle level description of their dynamics exists to date. Such a model would have tremendous impact on understanding skyrmion dynamics by theoretical analysis and computational modeling. Here we derive the equation of motion from a microscopic continuum model and obtain the short-range interaction between skyrmions, and the interaction between skyrmions and defects. Skyrmions also experience a Magnus force perpendicular to their velocity due to the underlying emergent electromagnetic field. We validate the equation of motion by studying the depinning transition using both the particle and the continuum models. By using the particle description, we explain the recent experimental observations of the rotation of a skyrmion lattice in the presence of a temperature gradient. We also predict quantum and thermal creep motion of skyrmions in the pinning potential.
Tunable Emergent Gauge Fields from Skyrmions in a Quasicrystalline Lattice
Department of Physics and Astronomy, The University of Tennessee（田纳西大学物理与天文学系）；Instituto de Física de Líquidos y Sistemas Biológicos, CONICET, Facultad de Ciencias Exactas, Universidad Nacional de La Plata（拉普拉塔国立大学精确科学学院液体与生物系统物理研究所，阿根廷国家科学研究委员会）；Departamento de Ciencias Básicas, Facultad de Ingeniería, UNLP（拉普拉塔国立大学工程学院基础科学系）；Neutron Scattering Division and Shull-Wollan Center, Oak Ridge National Laboratory（橡树岭国家实验室中子散射处和舒尔-沃兰中心）；Centro Atómico Bariloche and Instituto Balseiro, CNEA（巴里洛切原子中心巴尔塞罗研究所，阿根廷核能委员会）；Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)（阿根廷国家科学研究委员会）；Instituto de Nanociencia y Nanotecnología CNEA-CONICET（CNEA-CONICET纳米科学与技术研究所）
Italian Institute of Technology（意大利理工学院）；University of Genoa（热那亚大学）；University of Groningen（格罗宁根大学）；RIKEN Center for Emergent Matter Science (CEMS)（理化学研究所 emergent matter science 中心）；Fundamental Quantum Science Program (FQSP), TRIP Headquarters, RIKEN（理化学研究所 基础量子科学计划（FQSP）TRIP总部）；Quantum Materials Theory（量子材料理论）
