Coexistence of superconductivity and antiferromagnetism in the Hubbard model for cuprates

摘要

Antiferromagnetism and d-wave superconductivity are the most important competing ground-state phases of cuprate superconductors. Using cellular dynamical mean-field theory for the Hubbard model, we revisit the question of the coexistence and competition of these phases in the one-band Hubbard model with realistic band parameters and interaction strengths. With an exact diagonalization solver, we improve on previous works with a more complete bath parametrization which is carefully chosen to grant the maximal possible freedom to the hybridization function for a given number of bath orbitals. Compared with previous incomplete parametrizations, this general bath parametrization shows that the range of microscopic coexistence of superconductivity and antiferromagnetism is reduced for band parameters for Nd2-xCexCuO4 (NCCO) and confined to electron doping with parameters relevant for YBa2Cu3O7-x (YBCO).