Skyrmions are topologically protected spin textures, characterized by a topological winding number $N$, that occur spontaneously in some magnetic materials. Recent experiments have demonstrated the capability to grow graphene on top Fe/Ir, a system that exhibits a two-dimensional skyrmion lattice. Here we show that a weak exchange coupling between the Dirac electrons in graphene and a two-dimensional skyrmion lattice with $N=\pm 1$ drives graphene into a quantum anomalous Hall phase, with a band gap in bulk, a Chern number $\mathcal{C}=2N$, and chiral edge states with perfect quantization of conductance $G=2N\frac{e^2}{h}$. Our findings imply that the topological properties of the skyrmion lattice can be imprinted in the Dirac electrons of graphene.

• Received 11 May 2015

DOI:https://doi.org/10.1103/PhysRevB.92.115433