1998/07/28 by M. M. Sanchez, M. M Sánchez, A. Avella +3
Materials Science · Mathematics · Physics and Astronomy · #Algebraic structures and combinatorial models #Organic and Molecular Conductors Research #Physics of Superconductivity and Magnetism #cond-mat.str-el
paper · pdf · doi:10.1209/epl/i1998-00478-8
published as Europhys. Lett. 44, 328 (1998) · 7 pages, 3 embedded Postscript figures, EuroTeX, submitted to EuroPhysics Letters
arxiv created 1998/07/28 · openalex publication_date 1998/11/01 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
The one-dimensional Hubbard model at half-filling is studied in the framework of the Composite Operator Method using a static approximation. A solution characterized by strong antiferromagnetic correlations and a gap for any non-zero on-site interaction U is found. The corresponding ground-state energy, double occupancy and specific heat are in excellent agreement with those obtained within the Bethe Ansatz. These results show that the Composite Operator Method is an appropriate framework for the half-filled Hubbard chain and can be applied to evaluate properties, like the correlation functions, which cannot be obtained by means of the Bethe Ansatz, except for some limiting cases.