Chirality-driven orbital magnetic moments as a new probe for topological magnetic structures

Abstract

When electrons are driven through unconventional magnetic structures, such as skyrmions, they experience emergent electromagnetic fields that originate several Hall effects. Independently, ground state emergent magnetic fields can also lead to orbital magnetism, even without the spin-orbit interaction. The close parallel between the geometric theories of the Hall effects and of the orbital magnetization raises the question: does a skyrmion display topological orbital magnetism? Here we first address the smallest systems with nonvanishing emergent magnetic field, trimers, characterizing the orbital magnetic properties from first-principles. Armed with this understanding, we study the orbital magnetism of skyrmions, and demonstrate that the contribution driven by the emergent magnetic field is topological. This means that the topological contribution to the orbital moment does not change under continous deformations of the magnetic structure. Furthermore, we use it to propose a new experimental protocol for the identification of topological magnetic structures, by soft x-ray spectroscopy.

17 pages, 5 figures, to be published in Nature Communications

References in corpus (4)

• Additive interfacial chiral interaction in multilayers for stabilization of small individual skyrmion at room temperature
• Electronic Orbital Currents and Polarization in Mott Insulators
• Real-Space Berry Phases - Skyrmion Soccer
• Real-Space and Reciprocal-Space Berry Phases in the Hall Effect of Mn${}_{1-\mathrm{x}}$Fe${}_{\mathrm{x}}$Si

Cited by in corpus (8)

• Theory of Current-Induced Angular Momentum Transfer Dynamics in Spin-Orbit Coupled Systems
• Prototypical topological orbital ferromagnet $\gamma$-FeMn
• Transverse Transport in Two-Dimensional Relativistic Systems with Non-Trivial Spin Textures
• Spin-orbit enabled all-electrical readout of chiral spin-textures
• A spin model for intrinsic antiferromagnetic skyrmions on a triangular lattice
• Unoccupied surface and interface states in Pd thin films deposited on Fe/Ir(111) surface
• Insights into the orbital magnetism of noncollinear magnetic systems
• Generalization of the Landau-Lifshitz-Gilbert equation by multi-body contributions to Gilbert damping for non-collinear magnets