Magnetism of an adatom on biased AA-stacked bilayer graphene

We study the magnetism of an adatom adsorbed on AA-stacked bilayer graphene (BLG) in both unbiased and biased cases using the Anderson impurity model. We find different magnetic phase diagrams for the adatom, depending on its energy level. The magnetic phase of the adatom varies from that in normal metals to that in graphene. This is because of the individual energy dependence of the density of states (DOS) of AA-stacked BLG and anomalous broadening of the adatom energy level. We also investigate the effect of a bias voltage on the DOS of AA-stacked BLG and show that adatom magnetization can be controlled by applying a bias voltage. This allows the possibility of using AA-stacked BLG in spintronic devices.