▎ 摘　　要

We have investigated the magnetic property of bilayer graphene adsorbed on BN/Co(111) by using the van der Waals density functional method. We found that the BN layer adjacent to the Co(111) substrate showed a buckling geometry while the BN layer next to the graphene layer became flat. According to previous results, a one-monolayer (ML) thickness of graphene on BN/Co(111) displayed a spin polarized state, but we observed that the half metallic state disappeared in bilayer graphene on BN/Co(111) while Co(111) was still half metallic as found in graphene(1ML)/BN/Co(111). We found that the surface graphene layer had a gap whereas the first interface graphene on BN/Co(111) showed an ordinary metallic state. Thus, we realized that the electronic structure of bilayer graphene grown on BN/Co(111) had been significantly altered compared with that of graphene(1ML)/BN/Co(111) system.