Ferrichiral skyrmions with sublattice-resolved chirality in extended Kitaev model in triangular lattice
The study investigates an extended Kitaev model on a triangular lattice, mapping it to an XXZ model plus Kitaev interactions. In the $\mathbb{Z}_2$ vortex regime, it reveals a novel ferrichiral skyrmion phase where two of three sublattices carry unit topological charge and the third is nonchiral. This unconventional state emerges at zero temperature without external fields or Dzyaloshinskii-Moriya interactions, suggesting a new route to skyrmion physics driven by frustrated exchange.