Eur. Phys. J. B 27, 127-134 (2002)
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

Abstract

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.