2004/01/31 by Alexander Reischl, A. Reischl, E. Müller‐Hartmann +2
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Physics of Superconductivity and Magnetism #Strong Light-Matter Interactions #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.70.245124
published as Phys. Rev. B 70, 245124 (2004) · 16 pages, 13 figures included. v2: Order of sections changed. Calculation and discussion of apparent gap in Section IV.A corrected
openalex publication_date 2004/12/28 · arxiv created 2005/01/04 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
The generalized t\text\ensuremath-J model conserving the number of double occupancies is constructed from the Hubbard model at and in the vicinity of half-filling at strong coupling. The construction is realized by a self-similar continuous unitary transformation. The flow equation is closed by a truncation scheme based on the spatial range of processes. We analyze the conditions under which the t\text\ensuremath-J model can be set up and we find that it can only be defined for sufficiently large interaction. There, the parameters of the effective model are determined.