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arXiv · 1704.06288

Topological domain walls in helimagnets

P. Schoenherr·J. Müller·L. Köhler·A. Rosch·N. Kanazawa·Y. Tokura·M. Garst·D. Meier
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Abstract

A magnetic helix arises in chiral magnets with a wavelength set by the spin-orbit coupling. We show that the helimagnetic order is a nanoscale analog to liquid crystals, exhibiting topological structures and domain walls that are distinctly different from classical magnets. Using magnetic force microscopy and micromagnetic simulations, we demonstrate that - similar to cholesteric liquid crystals - three fundamental types of domain walls are realized in the helimagnet FeGe. We reveal the micromagnetic wall structure and show that they can carry a finite skyrmion charge, permitting coupling to spin currents and contributions to a topological Hall effect. Our study establishes a new class of magnetic nano-objects with non-trivial topology, opening the door to innovative device concepts based on helimagnetic domain walls.

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P. Schoenherr, J. Müller, L. Köhler, A. Rosch, N. Kanazawa, Y. Tokura, M. Garst, D. Meier. 2017-04-20. Topological domain walls in helimagnets. https://doi.org/10.1038/s41567-018-0056-5

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