Ferromagnetic Weyl semimetal phase and anomalous Hall effect in stacked Kagome lattice

Recently, Weyl semimetals, which have three-dimensional linear dispersions near the Fermi energy have been intensively investigated. Especially, ferromagnetic Weyl semimetals are drawing attentions as a system which implements some novel transport phenomena such as the anomalous Hall effect. It is reported that ferromagnetic Weyl phase is realized in stacked Kagome material Co₃Sn₂S₂ by experiment and first principle calculation. In this presentation, we study the electronic state and the transport properties including the anomalous Hall effect by constructing an effective tight binding Hamiltonian. We focus on d orbits of cobalt which form Kagome ABC stacked structure (Shandite) as an effective model and compute its electronic state. As a result, we detect ferromagnetic Weyl semimetal phase. Furthermore, in order to reveal the transport property, we compute the anomalous Hall conductivity by using the Kubo formula. The Hall conductivity becomes large when the Fermi energy resides around the Weyl points.