https://doi.org/10.1140/epjb/e20020137
Flow to strong coupling in the two-dimensional Hubbard model
1
Theoretische Physik, ETH-Hönggerberg, 8093 Zürich, Switzerland
2
Theoretische Physik, Universität Leipzig, 04109 Leipzig, Germany
Corresponding author: a carsten@mit.edu
Received:
23
January
2002
Published online: 15 May 2002
We extend the analysis of the renormalization group flow in
the two-dimensional Hubbard model close to
half-filling using the recently developed temperature flow
formalism. We investigate the interplay of d-density wave and
Fermi surface deformation tendencies with those towards d-wave
pairing and antiferromagnetism. For a ratio of next nearest to
nearest neighbor hoppings, , and band fillings where the
Fermi surface is inside the Umklapp surface, only the d-pairing
susceptibility diverges at low temperatures. When the Fermi surface
intersects the Umklapp surface close to the saddle points, d-wave
pairing, d-density wave, antiferromagnetic and, to a weaker
extent, d-wave Fermi surface deformation susceptibilities grow
together when the interactions flow to strong coupling. We interpret
these findings as indications for a non-trivial strongly coupled
phase with short-ranged superconducting and antiferromagnetic
correlations, in close analogy with the spin liquid ground state in
the well-understood two-leg Hubbard ladder.
PACS: 71.10.Fd – Lattice fermion models (Hubbard model, etc.) / 74.72.-h – High-Tc compounds
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2002