Electron- versus hole-doping in the 2D t-t' Hubbard model

Carsten Honerkamp A

Adriana Moreo, Daniel Duffy

Daniel Duffy, Adriana Moreo

Enrico Arrigoni, Maria Daghofer, Markus Aichhorn +1 more

David Eichenberger, D. Baeriswyl

A variational Monte Carlo calculation is used for studying the ground state of the two-dimensional Hubbard model, including hopping between both nearest and next-nearest neighbor sites. Superconductivity with d-wave symmetry is found to be restricted to densities where the Fermi surface crosses the magnetic zone boundary. The condensate energy is much larger for hole doping than for electron doping. Superconductivity is kinetic energy driven for hole doping, but potential energy driven for electron doping. Our findings agree surprisingly well with experimental data for layered cuprates, both for electron- and hole-doped materials.

Adriana Moreo, Daniel Duffy

The electronic momentum distribution n(k) of the two dimensional Hubbard model is studied for different values of the coupling U/t, electronic density 〈n〉, and temperature, using quantum Monte Carlo techniques. A detailed analysis of the data on 8 × 8 clusters shows that features consistent with hole pockets at momenta k = ( ± π