Spin-polarized transport through a domain wall in magnetized graphene

Atomically thin two-dimensional layer of honeycomb crystalline carbon known as graphene is a promising system for electronics. At charge neutrality it has a pointlike Fermi surface, which is very sensitive to external potentials and can be easily doped with either electrons or holes. Zeeman magnetic field parallel to the graphene layer splits electron bands according to spin polarization and creates geometrically congruent circular Fermi surfaces of particle and hole type for spins down and up, respectively. Hence, a fully spin-polarized transport in both electron and hole channels could be realized, presenting an opportunity for developing graphene-based spintronic devices. In particular, if spin polarization is achieved by virtue of the proximity effect in graphene in contact with magnetic layer, a domain wall (DW) separating regions with opposite spin polarizations could act either as a spin flipper allowing controllable rotation of spin polarization of electric currents or as a spin filter (spin rectifier). Here we consider ballistic passage of spin-polarized charge carriers in magnetized graphene through such a DW and analyze different regimes of spin-dependent refraction and reflection as a function of chemical potential and the thickness of the DW.