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arXiv · 2310.10834

Three-sublattice antiferro-type and ferri-type skyrmion crystals in centrosymmetric magnets

Satoru Hayami
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Abstract

We numerically investigate the stability of the skyrmion crystals in a centrosymmetric lattice structure by focusing on the role of magnetic frustration arising from the multi-sublattice degree of freedom. By analyzing an effective three-sublattice spin model with the antiferromagnetic exchange interaction between different sublattices and the momentum-resolved exchange interaction between the same sublattice based on the simulated annealing, we find that various skyrmion crystal phases with sublattice-dependent skyrmion numbers are stabilized with and without an external magnetic field depending on the model parameters: two ferro-type skyrmion crystal phases with the skyrmion numbers of one and two, two ferri-type skyrmion crystal phases, and one antiferro-type skyrmion crystal phase. Our results indicate that the multi-sublattice degree of freedom brings a further intriguing possibility of inducing exotic skyrmion crystal phases.

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Satoru Hayami. 2023-10-16. Three-sublattice antiferro-type and ferri-type skyrmion crystals in centrosymmetric magnets. https://doi.org/10.1103/physrevb.109.014415

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