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arXiv · 1302.1994

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

A. O. Sboychakov·A. L. Rakhmanov·A. V. Rozhkov·Franco Nori
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Abstract

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 an undoped antiferromagnetic insulator and a metal 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.

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A. O. Sboychakov, A. L. Rakhmanov, A. V. Rozhkov, Franco Nori. 2013-02-08. Metal-insulator transition and phase separation in doped AA-stacked graphene bilayers. https://doi.org/10.1103/physrevb.87.121401

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