Gate-voltage-dependent Landau levels in AA-stacked bilayer graphene

The effects of gate voltage V g on the Landau levels (LLs) of the AA-stacked bilayer graphene are investigated by the Peierls tight-binding model. A uniform perpendicular magnetic field ( B 0 ) produces two groups of LLs. V g can raise the threshold LL energies, increase the quantum numbers of the LLs nearest to the chemical potential, and modify the LL spacing. An energy gap is induced by B 0 , and it has an oscillatory dependence on V g and B 0 . There exist semiconductor-semimetal transitions at certain critical gate voltages. Some carriers are transferred between similar sublattices on the two different layers. On the other hand, the main features of the Landau wave functions remain unchanged.