Physical review. B, Condensed matter
High-temperature expansion for the single-band Hubbard model
Jon Henderson, J. Oitmaa, M. C. B. Ashley
Abstract
We study the single-band Hubbard model via high-temperature expansions to order (\ensuremath{\beta}t${)}^{9}$ for the standard two- and three-dimensional lattices. Series are derived for the grand potential and for the ferromagnetic susceptibility, for general values of the Coulomb repulsion parameter U and electron density n. The series are difficult to analyze with any degree of precision, but estimates are obtained for the ferromagnetic critical temperature.