Strong-coupling expansion for the Hubbard model in arbitrary dimension using slave bosons

Abstract

A strong-coupling expansion for the antiferromagnetic phase of the Hubbard model is derived in the framework of the slave-boson mean-field approximation. The expansion can be obtained in terms of moments of the density of states of freely hopping electrons on a lattice, which in turn are obtained for hypercubic lattices in arbitrary dimension. The expansion is given for the case of half-filling and for the energy up to fifth order in the ratio of hopping integral $t$ over on-site interaction $U$, but can straightforwardly be generalized to the non-half-filled case and be extended to higher orders in $t/U$. For the energy the expansion is found to have an accuracy of better than $1\%$ for $U/t\ge 8$. A comparison is given with an earlier perturbation expansion based on the Linear Spin Wave approximation and with a similar expansion based on the Hartree-Fock approximation. The case of an infinite number of spatial dimensions is discussed.

12 pages, LaTeX2e, to be published in Phys. Rev. B

References in corpus (2)

• Low-Temperature Behavior of the Large-U Hubbard Model from High-Temperature Expansions
• Helicity Modulus and Effective Hopping in the Two-Dimensional Hubbard Model Using Slave-Boson Methods

Cited by in corpus (1)

• Quantum Monte Carlo Study of the Disordered Attractive Hubbard Model