2002/02/07 by T. Schauerte, P. G. J. van Dongen
Mathematics · Physics and Astronomy · #Advanced Condensed Matter Physics #Anisotropy #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Coupling (piping) #Geometry #Hubbard model #Materials science #Mathematical physics #Mathematics #Perturbation (astronomy) #Perturbation theory (quantum mechanics) #Phase (matter) #Phase diagram #Physics #Physics of Superconductivity and Magnetism #Quantum electrodynamics #Quantum mechanics #Superconductivity #Symmetry (geometry) #Symmetry breaking #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.65.081105
published as Phys. Rev. B 65, 081105(R) (2002)
openalex publication_date 2002/02/07 · arxiv created 2002/02/26 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The phase diagram of the Hubbard model is studied at weak coupling in two and three spatial dimensions. It is shown that the N'eel temperature and the order parameter in d=3 are smaller than the Hartree-Fock predictions by a factor of q=0.2599. For d=2 we show that the self-consistent (sc) perturbation series bears no relevance to the behavior of the exact solution of the Hubbard model in the symmetry-broken phase. We also investigate an anisotropic model and show that the coupling between planes is essential for the validity of mean-field-type order parameters.