2004/07/16 by N. Blümer, Eva Kalinowski, E. Kalinowski · 2 citations
Physics and Astronomy · #Advanced Condensed Matter Physics #Physics of Superconductivity and Magnetism #Theoretical and Computational Physics #cond-mat.str-el
paper · pdf · doi:10.1016/j.physb.2005.01.179
published as Physica B 359, 648 (2005) · 2 pages, 5 figures, submitted to SCES '04
arxiv created 2004/07/16 · openalex publication_date 2005/02/17 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We present a new method, ePT, for extrapolating few known coefficients of a perturbative expansion. Controlled by comparisons with numerically exact quantum Monte Carlo (QMC) results, 10th order strong-coupling perturbation theory (PT) for the Hubbard model on the Bethe lattice is reliably extrapolated to infinite order. Within dynamical mean-field theory (DMFT), we obtain continuous estimates of energy E and double occupancy D with unprecedented precision O(10-5) for the Mott insulator above its stability edge Uc1=4.78 as well as critical exponents. In addition, we derive corresponding precise estimates for E and D in the metallic ground state from extensive low-temperature QMC simulations using a fit to weak-coupling PT while enforcing thermodynamic consistency.