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Marginal Fermi liquid behaviour in the d=2 Hubbard model with cut-off

V. Mastropietro
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Abstract

We consider the half-filled Hubbard model with a cut-off forbidding momenta close to the angles of the square shaped Fermi surface. By Renormalization Group methods we find a convergent expansion for the Schwinger function up to exponentially small temperatures. We prove that the system is not a Fermi liquid, but on the contrary it behaves like a Marginal Fermi liquid, a behaviour observed in the normal phase of high T_c superconductors.

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V. Mastropietro. 2002-11-07. Marginal Fermi liquid behaviour in the d=2 Hubbard model with cut-off. https://doi.org/10.1007/s000230200002

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