1302.1994 (A. O. Sboychakov et al.)

Metal-insulator transition and phase separation in doped AA-stacked
graphene bilayers    [PDF]

A. O. Sboychakov, A. L. Rakhmanov, A. V. Rozhkov, Franco Nori

We investigate the doping of AA-stacked graphene bilayers. Applying a mean field theory at zero temperature we find that, at half-filling, the bilayer is an antiferromagnetic insulator. Upon doping, the homogeneous phase becomes unstable with respect to phase separation. The separated phases are undoped antiferromagnetic insulating and metallic with a non-zero concentration of charge carriers. At sufficiently high doping, the insulating areas shrink and disappear, and the system becomes a homogeneous metal. The conductivity changes drastically upon doping, so the bilayer may be used as a switch in electronic devices. The effects of finite temperature are also discussed.

View original: http://arxiv.org/abs/1302.1994