Competition between Antiferromagnetism and Superconductivity in High   $T_c$ Cuprates
  Using variational cluster perturbation theory we study the competition between d-wave superconductivity (dSC) and antiferromagnetism (AF) in the the t-t'-t''-U Hubbard model. Large scale computer calculations reproduce the overall ground state phase diagram of the high-temperature superconductors as well as the one-particle excitation spectra for both hole- and electron-doping. We identify clear signatures of the Mott gap as well as of AF and of dSC that should be observable in photoemission experiments. 
David Senechal, P.-L. Lavertu, M.-A. Marois, and A.-M.S. Tremblay