2011/02/17 by A. A. Katanin, Andrey A. Katanin, H. Yamase +3 · 2 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Ferromagnetism #Ground state #Hubbard model #Magnetism #Organic and Molecular Conductors Research #Phase diagram #Physics of Superconductivity and Magnetism #Superconductivity #Van Hove singularity #cond-mat.str-el
paper · pdf · doi:10.1143/jpsj.80.063702
published as J. Phys. Soc. Jpn. 80, 063702 (2011) · 9 pages, 3 figures
arxiv created 2011/02/17 · openalex publication_date 2011/06/03 · arxiv updated 2015/05/27 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We study a ferromagnetic tendency in the two-dimensional Hubbard model near van Hove filling by using a functional renormalization-group method. We compute temperature dependences of magnetic susceptibilities including incommensurate magnetism. The ferromagnetic tendency is found to occur in a dome-shaped region around van Hove filling with an asymmetric property: incommensurate magnetism is favored near the edge of the dome above van Hove filling whereas a first-order-like transition to the ferromagnetic ground state is expected below van Hove filling. The dome-shaped phase diagram is well captured in the Stoner theory by invoking a smaller Coulomb interaction. Triplet p-wave superconductivity tends to develop at low temperatures inside the dome and extends more than the ferromagnetic region above van Hove filling.