Detectable spin–orbit splitting in Ni doped graphene

• Detectable spin–orbit splitting can be produced in Ni doped graphene.
• The spin–orbit splitting can be up to about 100 meV near the Fermi level.
• The spin–orbit coupling constant can be positive or negative for different bands.
• The large spin–orbit splitting is induced by the dyz   and dz2dz2 states.

Spin–orbit (SO) splitting in Ni doped graphene was examined on the basis of density-functional theory. Due to the inversion asymmetry induced by the graphene–Ni interaction, Rashba-type SO effect would be expectable in the Vacuum/Ni-monolayer/Graphene structure. Surprisingly, detectable SO splitting can be obtained in the systems without heavy metals. The SO splitting can be up to about 100 meV near the Fermi level. The Rashba parameter is about 0.17 eVÅ/ħ, half of that of the Au(111)Au(111) surface state. Interestingly, the SO coupling constant can be positive or negative for different bands.