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arXiv · 1511.08244

Topological spin waves in the atomic-scale magnetic skyrmion crystal

A. Roldán-Molina·A. S. Nunez·J. Fernández-Rossier
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Abstract

We study the spin waves of the triangular skyrmion crystal that emerges in a two dimensional spin lattice model as a result of the competition between Heisenberg exchange, Dzyalonshinkii-Moriya interactions, Zeeman coupling and uniaxial anisotropy. The calculated spin wave bands have a finite Berry curvature that, in some cases, leads to non-zero Chern numbers, making this system topologically distinct from conventional magnonic systems. We compute the edge spin-waves, expected from the bulk-boundary correspondence principle, and show that they are chiral, which makes them immune to elastic backscattering. Our results illustrate how topological phases can occur in self-generated emergent superlattices at the mesoscale.

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A. Roldán-Molina, A. S. Nunez, J. Fernández-Rossier. 2015-11-25. Topological spin waves in the atomic-scale magnetic skyrmion crystal. https://doi.org/10.1088/1367-2630%2F18%2F4%2F045015

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