Non - Fermi Liquid Behaviour of Electrons in the Half - filled Honeycomb Lattice ( A renormalization group approach )
نویسندگان
چکیده
A system of electrons in the two-dimensional honeycomb lattice with Coulomb interactions is described by a renormalizable quantum field theory similar but not equal to QED 3. Renormalization group techniques are used to investigate the infrared behavior of the system that flows to a fixed point with non-Fermi liquid characteristics. There are anomalous dimensions in the fermionic observables, no quasiparti-cle pole, and anomalous screening of the Coulomb interaction. These results are robust as the Fermi level is not changed by the interaction. The system resembles in the infrared the one-dimensional Luttinger liquid.
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