IOP Publishing, New Journal of Physics, 4(18), p. 045015, 2016
DOI: 10.1088/1367-2630/18/4/045015
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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. ; Fondecyt 1150072 Fondo de Innovacion para la Competitividad-MINECON ICM P10-061-F Anillo ACT 1117 Financiamiento Basal para Centros Cientificos y Tecnologicos de Excelencia FB 0807