Dynamics of holes and long-range order in Hubbard model with infinite repulsion

Ju. V. Mikhailova

J.-B. Bru, de Siqueira Pedra, W.

The aim of the current paper is to illustrate, in a simple example, our recent, very general, rigorous results on the dynamical properties of fermions and quantum-spin systems with long-range, or meanfield, interactions, in infinite volume. We consider here the strong-coupling BCS-Hubbard model studied, because this example is very pedagogical and, at the same time, physically relevant for it highlights the impact of the (screened) Coulomb repulsion on (s-wave) superconductivity.

V. Ya. Krivnov, А. А. Овчинников, Vladyslav O. Cheranovskii

Mark Jarrell, Thomas Pruschke

J.-B. Bru, W. de Siqueira Pedra

The aim of the current paper is to illustrate, in a simple example, our recent, very general, rigorous results [1, 2] on the dynamical properties of fermions and quantum-spin systems with long-range, or mean-field, interactions, in infinite volume. We consider here the strong-coupling BCS-Hubbard model studied in [3, 4], because this example is very pedagogical and, at the same time, physically relevant for it highlights the impact of the (screened) Coulomb repulsion on ( $$s$$ -wave) superconductivity.

J. M. P. Carmelo

The Hubbard model on a square lattice is one of the most studied condensed-matter quantum problems.Here we find evidence that for intermediate $U/4t$ values and a hole-concentration range $x\in (x_c,x_*)$ the ground state of the Hubbard model on the square lattice perturbed by weak three-dimensional (3D) uniaxial anisotropy has long-range d-wave superconducting order. Here $t$ is the effective nearest-neighbor transfer integral and $U$ the effective on-site repulsion. The lower critical concentration $x_c$ involves the Ginzburg number Gi and is approximately given by $x_c\approx {\rm Gi}+x_0\approx 0.05$. Here $x_0