Phase diagram of the half-filled 3D Hubbard model

Abstract

The antiferromagnetic Ne\'el temperature ${T}_{N}$ is calculated as a function of the Coulomb interaction U for a half-filled 3D Hubbard model. Numerical results are given for the specific heat and staggered magnetic suspectibility on periodic lattices ranging from ${4}^{3}$--${10}^{3}$ sites, and used to determine ${T}_{N}$. The size dependence of the results suggests that the transition is weakly first order at small to intermediate values of U.