Chiral gauge field in fully-spin polarized Weyl semimetal with magnetic domain walls

Modulation of magnetization in magnetic Weyl semimetals leads to the shift of Weyl points in momentum space, which effectively serves as the chirality-dependent gauge field for the Weyl fermions. Here, we theoretically study such a magnetization-induced chiral gauge field, in a fully spin-polarized Weyl ferromagnet Co₃Sn₂S₂. From a tight-binding model of Co₃Sn₂S₂ on stacked kagome lattice with magnetism, we calculate the magnetization-dependent evolution of the Weyl points in momentum space, resulting in the chiral gauge field. In the presence of the magnetic domain wall structure, we evaluate the chiral magnetic field arising from the spatial profile of the chiral gauge field. We find that a magnetic domain wall in Co₃Sn₂S₂ gives rise to a giant chiral magnetic field for the Weyl fermions, which reaches the order of a few hundred tesla to induce the Landau quantization. Such a giant chiral magnetic field may also influence the novel transport phenomena, such as the charge pumping by the domain wall motion, compatible with the spin-motive force.