A First-Principles Investigation of the Carrier Doping Effect on the Magnetic Properties of Defective Graphene

The carrier doping effects on the magnetic properties of defective graphene with a hydrogen chemisorbed single-atom vacancy (H-GSV) are investigated by performing extensive spin-polarized first-principles calculations. Theoretical results show that the quasi-localized p_z-derived states around the Fermi level are responsible for the weakened magnetic moment (MM) and magnetic stabilized energy (MSE) of the H-GSV under carrier doping. The mechanism of reduced MSE in the carrier doped H-GSV can be well understood by the Heisenberg magnetic coupling model due to the response of these p_z-derived states to the carrier doping. Within the examined range of carrier doping concentration, the total MM of H-GSV is always larger than 1.0μ_B with μ_B representing the Bohr magneton, which is mainly contributed by the localized sp² states of the unsaturated C atom around the vacancy. These findings of H-GSV provide fundamental insight into defective graphene and help to understand the related experimental observations.