Interactions and phase transitions on graphene's honeycomb lattice.
نویسنده
چکیده
The low-energy theory of interacting electrons on graphene's two-dimensional honeycomb lattice is derived and discussed. In particular, the Hubbard model in the large-N limit is shown to have a semimetal-antiferromagnetic insulator quantum critical point in the universality class of the Gross-Neveu model. The same equivalence is conjectured to hold in the physical case N=2, and its consequences for various physical quantities are examined. The effects of the long-range Coulomb interaction and the magnetic field are discussed.
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عنوان ژورنال:
- Physical review letters
دوره 97 14 شماره
صفحات -
تاریخ انتشار 2006