Fig. 6. Spin-dependent band calculations for different electrodes taken independently.

In all panels, the density of states (DOS) projected on graphene is represented in blue (red) for majority (minority) spins plotted against energy (E) relative to Fermi energy (E_F). Positive (negative) spin polarization (P_c) of the hybridized/proximitized graphene layer is depicted in turquoise (gold). First, isolated interfaces alone have been calculated for a Ni/Gr, b Co/Gr, and c Co/Gr with a strong epitaxial interaction. Negative spin polarizations are derived in a and b cases, as expected from theoretically described spin filtering effects at FM/Gr interfaces. This is in-line with the negative spin polarization measured from Fig. 2 where Ni(111)/graphene is isolated from Co by the Al₂O₃ tunnel barrier.